Tank's are badly designed in this game, from playstyle (you are basically behaving as a dps that pops cd's for busters. Unlike the active mitigation that most other MMO's now have moved to, FFXIV is largely old school/passive mitigation) to the item mechanics (the only tank only stat, parry, is one that every tank seeks to avoid because of how little it does) or itemization (the entire issue with our right sides, with extra vitality only being useful for a brief window, making melded accesories the best option ---something that no class deals with. Ironically once you get melded gear, you will end up getting very bored as a raider as 5 of your item slots don't get upgraded).

Tanking is also frankly, boring--once you learn the mechanics of a fight (which are well designed and fantastic) the actual act of 'tanking' is incredibly boring, leading you to mostly just joining the dps to race to kill the boss. In other games, a great tank can heavily reduce their incoming damage second to second with great skill---and while damage does come, its secondary after actively mitigating down the incoming damage.