Really bigger updates obviously require a major version bump to signify to users that there is potential stability or breakage issues expected.
If your software is following semver, not necessarily. It only requires a major version bump if a change is breaking backwards compatibility. You can have very big minor releases and tiny major releases.
there was more time for people to run pre-release versions if they are adventurous and thus there is better testing
Again, by experience, this is assuming a lot.
Eh, I’m about the same age as OP, I don’t have to get to 50 to know that I’d take my parents’ economic context over the two crashes. The rest… For many reasons, if medicine does some miraculous leap forward by then, maybe I’ll still wish I got a lot more left to go by then.