It wouldn't be enough to run that FF14 homebrew in any old DnD campaign, no. It'd HAVE to be Eorzea. You'd (or I) would need to overhaul any modules you planned on using pretty thoroughly to keep that Feels Good momentum going.
Which... Don't get me wrong. One of the pet projects I have on the backburner is seeing if I could overhaul Storm King's Thunder to be about Primals rather than giants. Or Out of the Abyss to deal more with Voidsent. OR. Rime of the Frostmaiden to be Ishgard focused.
I'm just also "GUYS PLEASE LET ME FINISH CUSTOMIZING AND RUNNING STRYXHAVEN FIRST. That's my main pet project at the moment, please let me tackle this one before I do something as crazy as an FF14 overhaul."
I have no strong opinions on module-based as a general thing, though they're not what I choose to run. but your comments come off very "because this is how I run, everyone must run this way, and look how much extra work it would be to use that, for the gameplay style I use as a GM."
Fine, fine, "you as the metaphorical you, which I will now spell out explicitly as the metaphorical to explain that I'm excited at this prospect but apparently this analogy doesn't fly with everyone else, so they have to come in and pop MY excitement balloon."