Is it nice to have a BRD or a MCH in higher level content? Sure. Is it mandatory? Hell no! Most of the classes have abilities that gain back TP and MP, and if you're not using them effectively, you shouldn't even be in high level content to begin with. If a Healer has to cast raise AT ALL in higher content, chances are your death wiped the raid anyway. So what is even the point? If you can't manage your resources then you're simply not ready for higher content, and that is the problem. Sure BRD/MCH can make certain classes more lazy and less dependent on their own abilities, but any skilled player playing any of those classes doesn't even need a BRD/MCH to be apart of the run to win it effectively. In short meaning, we get nerfed for having abilities, that are fundamentally luxury in the greater scope of the game.