I'm not sure why people get
so hung up over a name that they just can't see beyond that.
I know that the name sets an expectation, and it would be shitty if they made the game out to be a certain thing, and then pulled the rug out from gamers unexpectedly. But in the case of DmC, it was very clear what the game was going to be right form the get go: they didn't 'hide' any of the changes, they put them out there from the time of the first trailer. And IMHO, it's a very good game. I think I probably enjoyed it more than DMC2 and DMC4, but maybe not as much as DMC1 and definitely not as much as DMC3. That said, I've enjoyed all of the DMC/DmC games.
This 'name' fixation isn't limited to just DMC games either. Hitman: Absolution and Syndicate (2012) both suffered the same backlash, despite both being great games IMHO (and I say that as somebody who really enjoys both of those game series). I don't mind if devs/publishers want to change up a formula slightly (rather than putting out the same damn game every few years), provided the final product is good. When someone says "this game would have been good with a different name", then to me that simply says that the game is good. That's what I'm looking for from a game