Overwatch's situation is different, however.
The issue there was discovered when they realized that players were blocking the highest ranked Widowmaker so much that the guy couldn't get into a match. That's a huge issue when you account the fact that Blizzard is trying to put Overwatch in the same catagory as Counter-Strike in competitive gaming, and the best players can't actually play the game from others frustratingly blocking them.
FFXIV isn't built on that. Sure, PVP exists here, but meeting a genuinely nasty person in your party and wanting to never deal with them again is more legitimate than "bro too OP, avoid."