I don't know what the issue really was. I think the players just didn't like my GMing style or something. I am just trying to make sense of this.
I thought there was sufficient data in your prior posts to deduce it.
The players who quit had the most powerful PCs in the party. Anytime you have players with significantly more powerful PCs, those players probably value power in the game over anything else (aka power gamers).
You directly neutralized them during combats, which goes against the kind of game a power gamer wants to have.
That is why they left. Game style preference mismatch.