Aggro combos impose limitations on job depth. It's like a less extreme version of the problem with healers; It's difficult to give them a proper rotation because they need to be able to potentially interrupt that 'rotation' at any time to heal without incurring major penalties, ergo they've always had the least amount of interesting options in terms of dealing damage. Tanks suffered from this to a lesser extent previously, and some jobs still haven't fully recovered from it.
The game had these when "aggro management" was a thing, and they weren't very exciting in practice. You just ended up voke/shirking at a scripted time, or asking your party to save their aggro dumps for that scripted time. It was still just a matter of pressing a button at a timestamp, it didn't really add the kind of dynamism people in this thread seem to be after.
