I had an issue with XIV freezing constantly mid-game ever since Dawntrail. It was to the point the game was near unplayable since it was happening a lot more frequently, within hours, as of recent. I had tried about every method I could try to fix the game, but to no avail. Up until recently, a friend who had the same issue as me told me how he fixed his issue with the game.

He instructed me to uninstall Microsoft OneDrive off my computer. Since I don't really use the application, I proceeded to do so and so far as of typing this out my game hasn't froze for the past couple of hours.
I hope this solution helps out others, it's such a very odd and specific issue and I don't know how widespread it is since I couldn't find anyone else talking about this problem.