A lot of things sometimes need to happen for large advances in "progress" to be made.
The Sopwith Camel was on it's way out in 1918, it was being replaced by the Sopwith Snipe among others and even the Snipe would have been replaced in due course in 1919 by the Sopwith Snapper had all gone according to plan. It didn't.
The Camel used a lot of engines but the average was a 130hp engine of about 16.3 liters that weighed 173KG. The Snipe used a 230hp engine of 24.9 liters that weighed 220kg, The Snapper used a 340hp 22.8 liter engine of about 270KG. This was the famous (or infamous) ABC Dragonfly that could have won the air war for the Germans in 1919. All these engines ran on fuel that was anywhere from 40 (common) to 70 (rare) Octane. and nobody knew which batch was which.
The put upon Bulldog used a 28.7 liter engine of 440hp that weighed around 800lbs It ran on 73-77 octane fuel and was supercharged, making it's rated power at 12,000ft and that rating was max continuous or at least 30 minute rating.
Yes the RAF used WW I left overs during the early 20s but both the aIrframes and engines wore out. The engine makers figured out how to make radials instead of rotaries and the fuel guys figured out the octane scale and how to measure and blend fuel to get what they wanted rather than try to get gas made from the crude of a particular oil field. Manufacturing of engines was also advancing. The Jupiter VIIs went through several models. The Jupiter VIIF going to forged alloy cylinder heads screwed and shrunk onto the steel barrels instead of trying to use an aluminium cooling "Muff" shrunk onto the a closed end steel cylinder. The Jupiter VII F.P. added pressure feed lubrication to the wrist pins in 1930. The Bulldog may still have been a biplane but it was 38mph faster than the Snapper and had 6,000ft more ceiling, it's engine was more reliable than anything made in WW I and went longer between overhauls.
This required not only better fuel but better metallurgy(it took years to find aluminium alloys with similar expansion rates as steel alloys), it took a better understanding of vibration, especially harmonic vibration (one of the main failings of the Dragonfly) and better cylinder cooling (another Dragonfly failing, a copper coating over the fins does NOT make up for not enough fin area to begin with).
The Bulldog was all metal construction with a fabric covering, a major advancement over the mostly wood framework of many WW II aircraft.
The 20s were a period of great advancement, or at least the behind the scenes advancement that made the progress of the 1930s possible. The Early 30s might well be criticized as with some of the knowledge/tools in place progress still didn't move forward very fast in some nations. The Lockheed Orion should have been a major wake-up call.
near the end of 1931, top speed 210mph at 6,000ft, cruised at 180mph while carrying 6 passengers (170lbs each) and 90lbs baggage, 100 gallons (US) of fuel was good for range of about 650 miles.