The part of the game that feels wrong right now probably more than anything is oddly enough the extreme content. It's pretty unpractical to try and apex gear multiple jobs to the point of handling the extreme content, meaning in order to get to do the content players must focus into a specific role. This was already the case before patch 2.1 with AF +1, but with the inclusion of the patch the situation has only grown worse. That and FFXIV ARR really shouldn't be hosting nightmare difficulty exclusive content. It's going to foster community face smashing and divide everyone up into cliques just like it has in every other game it has been introduced to.
Seriously taking a step back and looking at the situation, there is something very wrong with people getting to the point that they can't take new players to content without having them watch 20+ minute boss tutorials, and then even boot said new players if they mess up more than three times. Is this really what we want the community to come down to? People smashing each others face in with sledge hammers because nightmare content is the end game standard?
Then there also is the problem that the core game doesn't emphasize a need for specific cross class skills, such as provoke or swift cast, so there are plenty of players that come to the end of the game and are forced to learn they need them through the school of hard knox. (Namely, entering a fight that requires boss swapping in the case of provoke, then getting berated by the group for not having it).
