Butcher doesn't believe killing the Supes would "Fix everything". Butcher doesn't care about "Everything". He believes you can't fix Vought, and you can't fix supes. Supes are inherently bad, the way they are created is inherently immoral, and he hates them.
And in neither the comic or the show are you supposed to agree with Butcher. You are shown explicitly that his views are myopic and based on his personal vendetta. That's the point.

Edit: He is literally the final villain. In the comics this is foreshadowed heavily by the chat with Mallory, where he explains mission creep of Special Operations with loose mission structures and directly invokes Butcher as an example of that. In the show they have like five seasons of telling you Butcher is bad, but then pulling back on it.

Edit 2: And in the comics right after he states his thesis of all supes being rotten psychopathic monsters, we cut to Super Duper a group of people who could not more obviously be a refutation of Butcher's point if they tried. They are a group of disabled superheroes who go on missions to literally rescue cats from trees. (And Garth Ennis' portrayal of them is of course incredibly ableist)

But there is no revolutionary moment here, at least not with the supes. Within the unierse of the show, the supes in large numbers sided with Homelander, Homelander's supe supremacy was a stand in for white supremacy. But add in the fact that, again, all of them are employed by a military contractor come media company come explicitly right wing political organisation. They're just not gonna be the revolutionary cadres you want.