The point was, the Japanese failed to down any of the B-17s at Pearl and there seemed to be an absence of the use of their cannons. Conversely, the SBDs arriving at Pearl (at the same time as the B-17s) were mauled. Perhaps I presented it wrong, the point I was trying to make, is that the bombers seemed to have made it through surprisingly well in spite of the situation but trying to attack Formosa would have most likely been a suicide mission.
Agree with the first part of your comment, and to give it greater emphasis, you could say that the Japanese failed to down even a single UNARMED B-17 incapable of firing back as they carried no ammo and their guns were stored for shipment. Per General Arnold's direct orders, no ammo was to be carried on the long flight from California so that the fuel load could be maximized. These aircraft, destined for the Philippines, were to be armed in Hawaii prior to continuing their mission. Four B-17Cs and eight B-17Es spaced 10 minutes apart made the flight to Hawaii. (p. 73,
7 December 1941 The Air Force Story)
Status of these 12 at 1845, 8 Dec 41: B-17Es 7 in commission, 1 repairable, B-17Cs 2 in commission, 1 repairable (later salvaged for parts), 1 destroyed. B-17C 40-2074, piloted by CPT Raymond T. Swenson, managed to land at Hickam. However, a strafing Zero ignited flares in the mid section creating a fire that burned the aircraft in two, and mortally wounded flight surgeon 1LT William R. Schick. From what I gather, Schick was the only casualty aboard the 12 B-17s.
Can't agree that an attack on Formosa would be a suicide mission. Much would depend on the altitude the bombers attacked from. Also, In reading the (highly recommended) Nov. 1, 2019 Airforce Magazine article
Disaster in the Philippines - Air Force Magazine ,
"According to information obtained after the war, the delay caused anxiety among the Japanese, who anticipated that B-17 strikes had been ordered and knew that their defenses were 'far from complete' and 'would have been ineffective against a determined enemy attack.'" The delay mentioned was the pause in the Japanese attack on the morning of 8 Dec due to fog.
Bear in mind the Japanese lacked radar early warning and there's no guarantee that high flying Fortresses would be detected from warships underway. I've read several Japanese accounts that surface forces were unaware of the presence of B-17s until bombs began to splash around, seemingly out of nowhere. Unlike the 12 unarmed B-17s caught in the Pearl Harbor attack, FEAF B-17s attacking Formosa would be fully armed.