I'll offer a very tepid defense of DMC2:

The only way to appreciate this game is through Lucia's campaign. I think a big reason the game is so maligned is because basically nobody bothered to play it, which is understandable - Dante is the main guy, cool, big sword, his campaign must be the definitive route. So they play that and - wow, that sucked. Delete.

But I'd argue that Lucia is the true protagonist of the game.

I don't know the specifics of the development, but to me, it feels like the game was designed around Lucia, but then at some point the game became a proper DMC sequel, so they made Dante playable. At least, that's how his campaign feels - like he was an extra character dropped in after the fact with little regard for his abilities. It's bad, but not even in an interesting way. Just boring.

But then, playing as Lucia, I was shocked as things suddenly made sense. I noticed enemies and bosses were designed to complement Lucia's moveset. It felt like an actual game. And, best of all, there's no infested chopper fight. The Lucia version is still mediocre, but it's coherent.