I think the better question is Complexity vs Clunkiness.

I personally, do like Complexity within a job. It makes the game more engaging especially when it has such a long GCD.

However, the game has a fair amount of Clunkiness that is trying to be passed off as Complexity.

By that I mean... Jobs like Bard, Astrologian and Ninja are complex. But they also flow pretty nicely. Like, Bard has approximately 1 million oGCD's to manage, but they weave into their GCD's seamlessly. Astrologian has some unfortunate annoyance via RNG, but the cards themselves fit into the job seamlessly. Ninja occasionally has to deal with some Mudra lag, but otherwise, they can easily weave their Ninjutsu between their attacks.

This allows them to be complex, just because of the extra inputs they require or how many skills they will fire off, or managing an atypical resource (Cards).

However, you also have jobs like Machinist, Monk and Dark Knight which create complexity through clunky mechanics.

This is stuff like how Machinist's oGCD's have animations that prevent double weaving (Also, the awkwardness that is Overheat duration ticking down the exact moment you reach 100 heat) this is compounded by the nature of them having specific 10 second windows to dump everything they possibly can.

Monk has Tornado Kick eating GL3 and RoF debuffing SkS that again, creates a situation where you have to do more complex series of actions, in order to deal with a negative aspect of using their skills (Most notably, having to try and regain GL3 as soon as possible so you can use your oGCD's and Demolish at maximum strength again).

While Dark Knight has the whole "Dark Arts Spam Dark Arts DA Dark Arts Before Dark Arts Every Dark Arts Action" thing as well as resource management systems that they don't have a ton of control over (Unlike say, how BLM can easily spend and regain MP very quickly. DRK requires spamming of a second stage combo skill to regain MP outside of Blood Weapon. They're also locked out of Blood Weapon when using Grit), which is again, not a nice flow.

So yeah, that's a thing. I personally would prefer it if more jobs were Complex but not Clunky.

That said, I don't mind playing a simpler job if it can have some fun feedback, such as landing big ol' crits when swinging an Axe around, or chunking into an enemy with Midare Setsugekka.

Heck, even "Simple" jobs can have a feeling of complexity. Such as how Red Mage is a very simple job, but it feels like a more complex one because of how it constantly makes you switch up what skills your using based on procs and their Mana resource.

Or how Black Mage is made more complex by its inability to move and cast so it becomes a skill to be able to position correctly to enable you to sling spells.

Heck, even Blue Mage can feel complex when you're doing stuff like weaving in 1 second cast spells to enable you to utilize your oGCD's without clipping.