I would note that the British pre war thinking hamstrung the British tanks. ... Maybe not all the time but the the practice of "The Charge" wasn't that that the tankers had not progressed past cavalry sabre thinking but they actually had a understanding of what the capabilities of their weapons were
Agreed it is never just one thing. The allies in the desert were fighting two different armies and although the Italian artillery was widely respected the average Italian infantry formation and to an extent armoured formation lacked artillery and anti tank fire power, more so than an allied infantry formation, so a charge could work quite well. The trouble being the persistent idea that tanks alone could do it and falling into traps pursuing an apparently retreating enemy instead of falling back into supported positions or even having that option as part of a coherent division let alone corps. Apart from what the armoured units did the doctrine resulted in plenty of infantry units putting in requests for tanks when German tanks were spotted or thought to be spotted or thought to be on the way, which did not help the idea of concentrated armour or the impression the infantry units made on the armoured ones. The desert offered few natural defences against a tank attack, your unit needed enough artillery and anti tank guns, I am not sure what the balance of firepower and defensive power would be if a panzer division hit an allied infantry division with only light field positions dug but I doubt it was good for the infantry.
The British decision on how far apart to lay rail tracks restricted the width of loads able to be carried therefore restricted the size of tank turret rings therefore the size/power of guns mounted. The defeats of 1940 meant the ready to go 6 pounder was put on hold, leaving the tanks with 2 pounders in the desert until 1942. All the cruiser tank designs came with Close Support options, the 3.7 inch howitzer, but doctrine said tanks fight tanks. Despite this the official organisation of an armoured brigade in 1940 had 166 tanks including 18 CS but it does not look like many CS versions made it to the desert. In early 1942 the Middle East tried an armoured brigade group with 3 battalions of tanks, 1 of infantry, 1 of artillery, plus 1 AT and 1 LAA batteries and the Grant was in service. As well as the armoured brigades there were tank brigades meant as infantry support and they were generally better at it.
The British had near zero armoured experience compared with the Germans, 1st Armoured was shipped to France but too late, there were other tank units present in France but they were meant as infantry support.
Operation Compass was the main source of information and those people were sent back and dispersed to be replaced by inexperienced forces. The loss of O'Conner did not help. Matildas in 1940/41 did very well as they were near immune to the normal anti tank guns leading to the idea that could keep advancing and in fact lead the attack. Rommel had to deal with the British counter attack in France, learning the value of the 88mm and when ordering his tanks to counter attack, being lured into a well done anti tank gun defence to stop such counter attacks.
The first Rommel attack mostly destroyed the British armoured units there, Brevity and Battleaxe lasted days and were heavy defeats of the forces involved, ending Matilda lead attacks. Then came Crusader, showing up defects at all levels as the allied force had grown from 1 corps to 2. Gazala at last saw the tanks have an effective HE ability in numbers but not in doctrine, plus the disadvantage the Grant could not go hull down to use the 75mm. Then on the first morning of Rommel's attack the concentrated DAK confronts sequentially 2 infantry and 2 armoured brigades, defeating each in turn as the allied high command kept to its belief Rommel was coming from the north, not south. Attempts to attack Rommel later in the battle had the same co-ordination problems.
I'd love to know exactly how many in 1940, 41, 42, but a reinforced division isn't 25,000 troops. Closer to half that especially if they aren't all at full strength. And we know that Crete was taken in 13 days exclusively with paratroopers (vs 40,000 defenders).
This is making it all about a working backwards from a conclusion, more airpower is the answer. I made the reinforced division comment with respect to the infantry only and in any case that failed to take into account the number of battalions, in fact the infantry at Malta was around 15 battalions, or the infantry equivalent of a weak corps. Also the state of the defenders at Crete including the thousands without weapons has been listed, but we still have the headline number, while trying to come up with reasons to take the headline number at Malta and reduce it. The allied position in Crete was worse than the position in Malta across the board, organised armed troops, supplies, heavy weapons, AA defences and defensive positions. It then comes down to how much damage can be done in the time available to attack the Malta defences. Also when it comes to an amphibious assault the main killers of the assault waves are the beach defences, not shore batteries, think Omaha. There would be few places in Malta where paratroopers could land without being in machine gun and rifle range during the descent.
Destroying or negating the shore batteries enables better naval gunfire support, then comes making sure the warships do not mess up the landing craft formations while trying to provide support, everything is moving, and having a system of trusted forward and/or air observers able to call in and direct the fire. So how good was this system in the Italian navy in 1942? Also how about the allied navy attitude at Normandy survival of invasion first, survival of ship second. The Germans had a good air support system in daylight, provided they could keep the communication links going and had enough aircraft able to do the mission well enough to overcome the invasion troops lack of heavy weapons. Remembering the need for follow up waves, with each wave hopefully expanding the bridge head enough to enable the next to land better organised and so able to fight better.
If you really want to decide the strength of the Malta defences look at Orders of Battle : Second World War, 1939-1945 / prepared by Lieutenant-Colonel. H. F. Joslen, 2 volumes, which tracks the British Army in WWII at battalion level. Things like the Falkland Island defences are in there.
The allies put a huge amount of effort into amphibious warfare and did a lot of learning from the assaults they did building to the big one of Overlord. Doing Overlord with 1942 allied amphibious doctrine would not be pleasant or nearly as successful.
Matildas were nice tanks for very early WW2, but look how long they lasted in the major battles in North Africa
How many 88 mm were coming with either the paratroops or the first amphibious assault waves?
Their lopsided victories, especially on the attack, came down largely to air power. (This is why they were so overly focused on dive bombing with regard to design planning in this era IMO, because they knew how key the Stuka had been to their early so-called "Blitzkrieg" victories ... which I know is a misnomer so don't go correcting me).
That statement is a main reason the Luftwaffe took on the Battle of Britain, that it was airpower that did it, one attack to destroy the target, move onto the next.
Not a Polish army lacking heavy weapons, badly outnumbered, being attacked on a wide front and for the inevitable reasons trying to defend the whole country, not falling back to better and shorter defences.
Not an allied High Command in France with minimal communication links, which meant by the time the command figured out where the Germans were they weren't, plus a ponderous staff system that meant orders issued were usually relevant to the situation the previous day or earlier. An allied army not trained in mobile warfare, then reserve formations not properly trained by the April 1940 standards and certainly not trained to deal with concentrated air attack.
Not a Soviet command purged of its best and handed stay and fight orders, or like the allies in France, sending orders that made sense a day or days ago, but not now. The German 1942 offensive in the USSR actually didn't capture that many prisoners, the lessons about timely withdrawal to avoid encirclement had been learnt.
6) Can't tanks shoot smoke or use machine guns or back away, or call in artillery?
Yes they can. If they have smoke mortars. If their machine gun is working and can hit the target (if they can see the target). If they can back away faster than the enemy tank or anti-tank gun can sight in and shoot them. Yes if the artillery can hit precisely where the enemy AT guns are before they can aim and shoot their gun.
The answer your own question format is not helping. In the desert any movement churned up lots of dust, making its own smoke screen. The reality is the towed anti tank guns could remain invisible to the tanks until well within killing range and they did, far more than the tanks managed to get out of the trap or call down accurate artillery to stop or defeat the anti tank guns. How long do you think it took to call in artillery on average? Then who was going to guide the fire onto the hostile positions?
In 1941 the allied infantry and artillery forces in the desert put the foundations down for the good wartime doctrine, forward observers with authority, artillery and infantry formations matched. The armour did not.
Air Power at the Battle Front by Gooderson uses the allied surveys and reports to give a good picture of the strengths and weaknesses of close support.