Saints Cap Moves: $30,305,932 cap space ….. 8 restructures, 3 extensions, 3 pay cut, 1 release [All current cap moves are in OP below line]

Yes, and that's on the coaching staff for not finding ways to help their rookie QB make those adjustments with plays that give him options when teams let loose their blitzers. Obviously the player takes some responsibility, but he was a rookie 5th round pick. The staff has to realize that and help him with the play calling.
It's possible the coaches did exactly that and Rattler still struggled.

Just like we don't know it wasn't the coaches, we also don't know it wasn't Rattler.