No idea who Asta is. Don't think I ever said Goku is interesting or not generic.
I'll bat for Luffy though. He's a way better protagonist than Deku, primarily because Oda doesn't attempt to add more to him where nothing is needed.
Luffy is a simpleton, an idiot whose mind runs a single track and who either by himself or via others, provides humor to the series. More than that though, his power, at a base level is far more interesting to play around with than a strength boost. Combined then, throughout One Piece, you get plenty of moments that are funny or interesting due to his simplistic nature and powers. But there aren't a lot of moments where you get the serious Luffy inner monologue because good god, that would be terrible.
Dekus powers aren't interesting. He comes off largely as an extremely low budget All Might. He's not really a funny protagonist, nor does he have the charm or charisma to carry the manga. His internal struggle is so largely simplistic that when I'm exposed to several chapters of him inner monologuing, it becomes largely a bore to read.
He might try to be a protagonist that uses his brains but since he's not actually all that smart, that fights aren't all that more interesting. Him using his "brain" largely amounts to using common sense and not being an idiot. When I think manga with smart fights, I think of something like Hunter x Hunter.
So to go back to it all, the Villain attacking arc? Yea, that shit was great. Because you had characters making an appearance in the manga that actually felt like they had a presence. Because Deku sure as hell doesn't. His origin story of him tagging along with his hot headed friend is perfect actually when you think about it. Because that's exactly what he still feels like. He's tagging along this manga ride with other characters, that are more interesting personality wise, have more interesting powers and have more charm and charisma in one panel than Deku does in a 100 some chapters.
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