A recurring theme has been an aircraft which took off flyable, becomes not flyable during the flight. 'Remarks about bungled aerobatics. This is not hitting the ground, hitting another object in the sky, or being shot up by the enemy, this is just airplane jams or breaks. How often has that happened, while an aircraft was being flown within it's approved maneuvering limits? For the few cases I can think of, by the time the pilot realized that they had completely bungled things, they were much too low to get out anyway.
I was required to wear a parachute while flying jumpers, I presume because of the risks of a jumper colliding with the tail, or, as explained to me, the risk of the aircraft tumbling, and my being thrown out (that did happen in Ontario decades back, I have no idea how). But, those are SOP type operations, where a risk is being managed. In GA, that risk is very very much less than the already low risk in jumper or such operations.
A very important part of being a good pilot is understanding risk. Be able to appreciate the balance of what could happen, vs severity, vs what is required to mitigate. The first and best way is to consider what everyone else doing it does, and do that! It must be working, they're still flying!
I have seen and do; wear fire resistant clothing all the time (natural fibers), wear hearing protection, wear my seat belt, wear a life jacket for over water flights, and carry an emergency kit appropriate to the route to be flown. My peers do these wise things. My peers don't wear a parachute for GA flying.
When I had to fly a Tiger Moth, it seems it was designed for the pilots to wear parachutes, there were deep depressions in the seat bottoms. 'No parachutes around. Three telephone books in the seat hole, and I was good to go.