I'm not going to claim that Capcom has no responsibility for how that game looks because, no matter what instruction they were under, they definitely do.
But I do think there is room for Marvel to mandate things like "don't let it look like a comic-book" that exacerbated the problem.
The game looks cheap. (visually it's unambitious and not impressive). And the roster is lackluster (Marvel's fault directly).
However, as to the game feeling cheap. Marvel licensing probably costs an arm and a leg. Not to mention they probably want revenue share on each copy sold additionally.
Capcom had to curb the game's production costs likely due to this.
Doesn't sound like an ideal relationship to make a great game then. I wonder how many things Marvel has in place that Insomniac can't do with Spider-Man, I know of the, he's not able to kill at all in the game part, but I wonder if there's anything else.