One thing to keep in mind though after coming from XI is this game isn't as community oriented and the game itself actually forces you to solo a fair bit throughout the story. So take for instance if Promyvion c. 2004 was in XIV, instead of doing it with 6-18+ people, the game would say "This duty has to be undertaken solo." So you end up getting used to being "alone" and relying on the Duty Finder for content. So while there's linkshells and guilds called Free Companies, you'll largely spend your gameplay in instances once you begin to unlock dungeons.
So it's not that anti-social, but the setup of the game kind of makes it so...in a sense, your actual server community doesn't matter too much in comparison to XI, but you'll still have chat channels and whatnot. Once you hit end-game depending on server, you'll see a lot of groups forming in Party Finder which is separate from Duty Finder. But you will be spending most of your content career using the Duty Finder, which grabs people from a set of servers for the content and people you most likely will never run into again unless they happen to be from your server.
This game is also strictly vertical progression in the sense joining now, you'll have plenty to do, but the content is fairly outdated so only the newest set of content is what matters most once you hit end-game. So depending on the type of player you are, XIV is really segmented.
If you're extremely casual and don't care about doing a lot of content - Balmung is probably the best bet if you can ever get onto it, next would be Gilgamesh (these are also Roleplaying servers unofficially.) Those are also as of now based on unofficial parsing, the 2 most populated NA servers, every other server has grown extremely quiet post Heavensward and even 3.1 update, but going down the list, Lamia, Sargatanas and Hyperion seems to also have a decent population.
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