It depends on what you are expecting.
Like the DMC example you used, if you actually play the game it's a great game. It has very fun combat, great graphics, fun bosses, over the top action - it's a DMC game at its core. It's just people didn't like the new character look and a few other things with it. Is that enough to say it shouldn't have been rebooted? I don't think so personally, as it's a very solid game.
I think that if a series gets a reboot, you need to go into it knowing it's a reboot. It most likely isn't from the same dev team and thus it's going to be different in some ways, some ways worse some ways better, go into it with a fresh mind. Even if it is the same dev team, it's still a reboot and you know they will try new things, take it for what it is (which means the game could suck or be good, but expectations should be set to trying something fresh going in).