I have to disagree that it could have gotten away with whatever it wanted. People made it their mission to destroy that game for being different, and by god, they succeeded.
Plus, it WAS an excellent game. It's not the inbred technical extravaganza that was DmC4, and I understand people wanted more of that, but that isn't what the game set out to be. It was completely successful in doing what it set out to do.
And Metroid Prime WAS fantastic.
BUT MEGAMAN GUYS, SRS
I doubt Mega Man fans would've ripped this apart though. Namely because we were used to Capcom whipping some new spinoff series together every so often. Besides, considering how I always viewed Mega Man Legends 1 as the closest thing to a 3D Metroid game of the PSX era, and that the ZX games were aiming to become Metroidvanias (and missing the mark by a wide margin), I don't think a Metroid Prime styled MMX game would've gotten boo'd out the door like you seem to think it would've.
As for DmC, what do the games have going for them in the first place? Let alone what they have going for them now that hasn't been done better by other series'? When you look at the new game, do you think it addressed the most fundamental issues surrounding DmC or do you think they just reskinned the series so that nothing really changed except everything in regards to the lore, setting, style, and spirit of the series?
To make a comparison, try imagining a Persona game set in an American College or a British Orphanage instead of a Japanese High School. The gameplay's the same but the atmosphere, the writing, and even the artstyle will probably be different (for the sake of the argument, let's assume that Atlus wont just have everything turnin' Japanese anyways). To make a less tortured comparison, try imagining a sequel to The World Ends With You
not being set in Shibyuya (or however its spelled), Japan and not featuring Noruma's designs or the accompanying atmosphere
, of any kind.
The tl;dr is that Capcom pretty much threw the baby out with the bathwater in regards to DmC and didn't bother to replace it with anything worthwhile. The game lost its identity and the reason why fans should choose it over anything made by Platinum Games.