The combat itself is very different from what I can tell. Outside of the fact they destroyed the iconic protagonist of the series the combat is not the same at all.
How you can say the gameplay isn't the same? The mission structure is the same. The items are the same. Orbs perform the same purpose. And combat is largely the same except for having different weapons and a few slightly different controls. So what about the gameplay is different/worse?
Not saying this game is bad, but certainly it isn't much like previous DMC games.
DMC1-4 had a sort of combat that no other third person beat-em-ups had. DMC: Devil May Cry itself doesn't have the same essence.