i have faith that pyro can theoretically be fixed to the point where it's no longer aids to play against
what makes tf2 great for me is the sense of personal agency, that like every death/frag/whatever I could've done something different (dodged the rocket better, pushed him when he was reloading etc.). I don't really get that feeling when I play against sniper though, just something about the one class that can sit as far back as possible on the map and dodge the fray just kinda irks me.
on the other hand though I like watching players like sheep and jukebox (though I imagine it'd be aids to play against them) rattle off 150 headshots like it's nothing. Maybe I just hate it when snipers hold an angle that you eventually have to cross with a full charge and you're just like "well shit better pray I get good rng and they miss or tf2 hitboxes save me"