I have been flying since 1980, had one heavy landing a number of years ago, when ASI failed in X country flight. 3000 hours in total solo.
I did however purchase a ASH 31 Mi and despite very good training from the agent in Australia.
Very early on in the flying of this glider I had a flight, both engine problems, refusal to start, and LX screen failing.
I switched to flying glider mode but still managed to land wheels up.
After considerable thought i now figure out the problem.
When stressed we go into fight of flight mode. Blood goes to the legs and leaves the brain. We thus go stupid. I recall looking at the undercarriage but did not say "Wheel down according to placard"
How many good pilots have you seen make stupid errors.
Perhaps you have hit the nail on the head, Older, over confident pilots in very complex aircraft