While he has a general disdain for them if you pay attention to his criticisms Garth highlights particular issues. Not all correct or unbiased, but still.
e.g. Heroes with a sense of self-importance who feel their city or world rests on their shoulders alone, the civilians and criminals are just nuisances to highlight their suffering. But then look at how Love Sausage is illustrated, not the crazy Russian with a big penis part, the part where his efforts were actually for something bigger than himself and is commended and pitied for the struggle not just his struggle.
Or the heroes who are rebellious and deviant for the sake of appearances or just because they're mental, where does it go? There's a difference between the belief that they portray the outliers of society and when they actually just exploit them. Using homosexuality, gender dysphoria, physical or mental disabilities, racism, rape, death as main attractions in a monthly minstrel show or an echo chamber or soapbox if they're deluded enough about their own gospel, instead of any actual point or progress.
Or heroes who do more self-indulgent theatrics than heroics, the kind who don't even see it as a labor or a representation of rebelling against the source of ostracization and oppression.They do it because they're bored. Vigilantism, the lives at stake are a game.
Watchmen similarly tackled these thing, just not quite so blunt and aggressively. Likely due to the times. Garth's problem if not the problem is likely less capes period and more cape writers proper.
Even as a fan of superhero media myself I can see a point and agree that a lot of it's just fucked because of fuckers. Though at the end of it like a lot of people have already said, love or hate, you don't need to take superheroes seriously one way or the other, they're not real. Even when I'm being serious about my criticisms I know we're not really having a serious chat here. It's just entertainment.