from what i've played so far you can mash one button to win (unless you have to do a qte sequence).
tbh, offensively you can mash one button in NG or DMC or Bayonetta too and beat down enemies. Square x 3 is a combo in all 4 games and does shitty damage in all 4. The reason you don't do 1 simple combo the entire game is because you want to do more damage and also so they don't get repetitive. If you watch speed run videos for all 3 games (not sure about Bayonetta; haven't seen any) you'll see that players pretty much just do the best 1-2 combos over and over. So yeah, it's not that different.
Defensively, in GoW you still have to roll, or block, or counter to not die. Same deal as in the other games. The enemies are just less aggressive than NG (DMC3 enemies are about as aggressive).
If you want to talk shit about GoW compared to the real action games that's easy:
-The hit detection is not super accurate like the others
-The boss patterns are not as intricate as the others
-The combo system is not as free-form or movelist as long as the others
-There are only a few enemy types compared to the other games with a bunch; enemies don't have much of a pattern in GoW, they just kinda sit back and attack when close.