Sure, but magic items don't need to be part of the game, spellbooks are sort of essential if you run into an enemy wizard (especially on their home turf).
Well, maybe a couple have used reasons 1 and 5 but I don't recall many posts where people just blurt out "Fighters are bad."
As for 2-4, sure those are
some of the reasons. Others, however, are more mundane:
- I want them to be able to do things at least as well as real life (the WR jumps, etc.). Yeah, I know, 5E isn't a sim, but still the rules are over-simplified IMO.
- I want them to be the best at things they should be the best at. Such as the expert rogue out wrestling the fighter... I could see the rogue escaping, sure, but not actually winning.
- I want them to be able to do some things that go beyond real life, since this is fantasy, like Xena for example. (Not overboard, but beyond.) For me this is the "heroic" level, not "superheroic". 200-ft jumps? Not for me, but 40-60 feet.. sure, especially in tiers 3 and 4.
As for the other pillars, each class historically had a role, but WotC's design allows most classes to break those roles and step on others' toes. I don't need a fighter to be as good at climbing as a rogue, but I wouldn't mind a ranger being able to, or to stealth as well, either, especially in favored terrain. Other than the Prodigy feat (which feats are optional and that is a racial feat anyway), there is no way to do this without houserules. There are other similar issues as well.
Now, for the people who want more extreme things, I agree it would be simpler in many ways to play a different game, but they don't really want to do that either.
Now, I know you aren't for enhancing fighters for combat. Other than some tactical improvements, I think fighters are pretty good (and others need to be brought back so fighters really can be the Best at combat). But what about exploration and social. You've said you don't want to step on others' toes, but aren't they stepping on the fighters' toes when it comes to combat??