And if we're being honest, not even Heavensward in general was complex for any job, let alone aggro management or otherwise. FFXIV has always been a relatively easy and forgiving game. It was less forgiving in Heavensward and had very punishing mechanics, like how vital positionals were, how much of a commitment Cleric Stance was, and other such examples, but so what? The game wasn't difficult to clear content with. Everyone was still able to progress the MSQ and clear all the major story questlines barring Coils of Bahamut (which no amount of simplified job design would help players clear until we got strong enough to solo them unsynched). So you occasionally wiped in a dungeon or alliance roulette every once in a while. You got up, and you did it again, and cleared it.
At the end of the day, the complexity of job design is and has always been largely optional for 95% of FFXIV.