I've never heard really heard anyone call Metallica "shitty" in general, just usually at Lulu or their post black album work. But even if you don't like them you have to at least respect and acknowledge their influence.
I just absolutely hate everything I've ever heard by Metallica haha. And that's a rarity for me, because usually bands that I don't like, I just ignore and don't care about them. But I literally actively hate Metallica. It's offensive to my ears. I don't really enjoy much of anything that could be called metal (excluding heavy metal pioneers e.g. Led Zeppelin, but that sound is so far removed from what metal is now that it hardly even applies) so I don't really care about their influence either haha.