End game raids and the Ex Primal series aren't intended to be queue up and clear in duty finder with no preparation. They are intended first and foremost for full groups to figure out over multiple runs. They added them to DF as a convenience after they were end-game relevant since cross-server party finder was not yet available. There is still a decent audience of people that attempt them (either synced, unsynced, or min-ilvl synced) for the challenge or to do it for glamours/orchestrion rolls/mats.

If you know the fights, they are all faceroll at 60 with a couple gotchas. (Insta-wipe on Ifrit/Levi/Ramuh, Divebombs on Twintania/Nael/Bahamut)

Every MMO has this "problem" with end-game content, once it is made irrelevant by places with better rewards, it dwindles away. FFXIV has actually handled it better than most by giving people reasons to go back and run old content (Roulettes, Anima, Wondrous Tails, Orchestrion, Glamour)