It’s a little bit of both. I don’t really hate hax as much as I play it up to be, but it’s definitely something that grinds my gears. I hate stupidly hax characters that ruin every bit of tension the instant they arrive. Which is mostly the latter category. Only exceptions are gods that are straight up not meant to be matched, like Arceus or the Marvel Abstracts or DC’s Endless.
I agree, I get with villains that they need to be haxed as hell so they be a threat and cause of tension to the heroes (Like Thanos or Dracula or Yhwach). But overly haxed heroes, unless they manage to get even more broken villains, often become a bunch of boring Mary Sue's.