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.
Yes, but it's IMHO not as clear cut. Some of the things we do because of our executive function disorder can be interpreted as us being assholes by those we interact with. One can act like an asshole at times and not intrinsically be one. Some things are perceived as assholeish by some people but not others.