it looks like you'd wail on one enemy for 3 minutes until it gives out.

Oh you'll wail a lot longer than that in some cases. Some of the summon boss fights took like 30~45 mins of wailing. And yes. The RPG elements are non existent, and the side quests are incredibly shallow and boring. You are spot on. No status effects, no elemental affinities, absolutely minimal equipment and weapon systems which amount to basically making a single number go up. It was honestly embarrassing as far as gameplay goes.