This is completely false. There is no 35 GCD rotation. There's nothing even close to that. And something like half of the jobs have proc based effects that have to be played around. As a simple example, Monk's rotation is simple, it's 6 positional skills with a few CDs you pop every 90s and a few CDs you weave in between those in a specific order so you maximize the damage hard hitting abilities do with max buffs up, a total of something like 12-14 buttons you use consistently for DPS. But when you pop brotherhood, you get chakras from other players in your party, which then give you forbidden chakra procs to spend in oGCD windows, but you have to avoid pushing your oGCDs with CDs out of your buff window.
Ranged DPS tend to have a lot more procs. Like Dancer is entirely dependent upon procs.
SMN has the most complicated rotation in the game, but like every other job, it's just weaving with CD popping and then doing things inside those CDs. It has phases, using everything takes a while, but your DPS doesn't tank because you clip something or drop an ability here or there because you're dodging, nor does GCD-level perfection matter outside of savage and ultimate progression, where your positioning is planned out for nearly the entire fight, letting you optimize your rotation and group wide CDs. Exactly like WoW.
This is just an unrolled example of playing SMN for the first CD set, but if you did the same in WoW, you'd see things like 15 fireball casts in a row or something: