This is literally, and I cannot stress this enough, LITERALLY how every class in the game works. Even Bards with all their random RNG functions off of minimizing delays and pressing the right button at the right time. What makes Black Mage so special that it demands an astronomically high SKILL FLOOR just as a barrier for entry? What does that skill floor offer the ceiling? Literally nothing. You don't play the class better working around AF/UI timers. You play using a largely set-in-stone rotation with rotational differences you can, actually, bake into the class if you wanted to. Both with and without timers, the class would still have the highest skill ceiling in the game. You'd have to actually remove fire 4's cast timer for the skill ceiling to come close to other classes. Literally remove the cast time from every spell except fire 4 and despair, and it would still be one of the hardest classes in the game to play because of how difficult it is to just stand still and cast in savage and especially ultimate content.
I want to stress that again. Literally every single spell except Fire 4 and Despair could be instant cast in a timerless black mage, and it would still be one of the hardest classes in the game to play because of just how long it has to stay still to maximize DPS. So what makes BLM so special that it deserves to actually be this difficult just to get into the class?
Hell, even with the AF/UI timers, the devs are trying their hardest to make sure BLM actually has a largely set in stone rotation. They want you to either do 3 F4 1 F1/paradox 3 f4 1 despair, or 2 f4 1 f1/para 2 f4 1 f3 2 f4 despair. If they wanted hypermeme, paradox never would have been added, and blizz 4 wouldn't have had its cast time reduced. They want you to paradox in AF phase pushing back to the above listed rotations. So how is it any different?