One thing is for sure: NFTs, cryptocurrencies and the like are far from a consensus. Even if you somehow like these things, you have to admit that not everyone likes them, far from it. This is a fact.

So, introducing such things to a beloved game or franchise... it's bound to fail. You'd be going against a very big chunk of your playerbase, from the most dedicated fans to the newest sprout. You could say that the profits in NFTs would compensate the loss in subs and other sources of revenue, but that's extremely unlikely (I'd say it's pretty much impossible).

That is to say... If you want to experiment with NFTs and the like, fine. You'll probably fail, but fine. Just remember to do it somewhere else, far from FFXIV or your other beloved games.