I don't think I've ever played an MMO that has so many well balanced choices that no two players are the same unless someone goes out of the way to build themselves like a clown just for the sake of being "unique". Most of the time there are clear superior choices, or at least choices that are marginally better in more situations, so everyone just tends to gravitate towards using those and leaves everything else to rot.

Not even XI had much more in the way of customization. Every class had certain subjobs that were "the best" and were more or less required for you to have (and you were sometimes denied groups if you didn't). The rest had mediocre or down right terrible synergy with your class so they weren't used. The same thing goes for the Merit system; you had "options", but nine times out of ten some were clearly better than others and it was silly to go out of your way and intentionally pick the inferior ones.

Don't be one of those people who gets taken in by the illusion of choice.

And don't compare MMOs to single player RPGs.