a whooooooole lot of ragequitting and calling miura a sjw-pandering hack/evil fetishizing homophobe/rape apologist on one side of the fandom, wild celebration on the other side
might depend how it goes canon too lol. like, guts and neogriffith improbably living happily ever after somehow? definitely the above
guts and griffith admitting to themselves and/or each other that they were/are still in love before one or both die in the final confrontation? i could see the majority of the berserk fandom hmphing and going “ugh fine” (or insisting it’s still platonic love or that he still loved casca more) instead of ragequitting or hating miura.
and probably a combination of the two if there was a kiss or something to demonstrate the non-platonicness of it lol