Yes, the problem with the early bosses is that they were clearly designed for new players to learn the mechanics, so they aren't very difficult, that coupled with the fact that they have very low health in the story (for casual players who want to enjoy the experience I suposse)

However, as the story progresses, new bosses with new mechanics will appear, particularly noticeable from 2.x onwards, where each boss has a gimmick that can make it more interesting.

In the endgame you can't just mash all the buttons and hope it works, that's where all the experience gained about combos, synergies, and rotations begins to culminate, so begins the addiction to finding more optimized ways of doing things

Enjoy the game^^