Quote Originally Posted by Hoaxtopher View Post
I'm pretty sure that the 24m number is the total accounts ever created for the game, not active subscriptions
I dunno, I was doing some googling, and it looks like more recent estimates have total number of subscribers at over 30 mil.

I was going to quote them, but most seems to be pulling that figure from here:
https://mmo-population.com/r/ffxiv