Back in the good old days the relic quests would've had you grinding for hours on end. But the FFXIV devs keep shooting themselves on the foot by putting relics at the very end of every patch cycle. So no, there's not much to do in the game unless you go out of your way to try whatever you haven't tried yet like collecting glamours, mounts, minions, sightseeing logs, doing all blue mage stuff, etc. But that's the hardcore crowd.

Most just usub due to there not being anything to do at end game. Relic grind is end game. Farming old primal mounts or looking around for minions is not really current level 80 end game.