Oh, the forums isn't really where the difference is. By definition, the forums are full of people who are there to complain.
The difference is in actual behavior in-game, and, frankly, the people who claim that WoW isn't toxic? They would fit right in there, and don't notice the toxicity from there...because they're part of it, and a main part of the source of it. Of course it's not toxic to them. They LIKE that kind of atmosphere, and they enjoy it. To them, that's how they want it all the time. They want to point out other people that they can be superior to. That's heaven to them. They just want to make that the norm in FFXIV.
The only saving grace here is that FFXIV won't allow it past a point. I think the devs main stance against damage meters and the like is that they know that if they were built in, they'd have to spend a lot more time (and money) enforcing the rules against mostly the people who clamored the most for the said damage meters and other similar things.
That way lies madness. No, let's not go there.