That would be asolutely true, if FFXIV was not frequently designed to have a coulple of tanks.
(Incoming FFXI comparison but not saying that this game need to be like FFXI, it's just an example)
In FFXI, at very-low level, NIN had only Utsusemi: Ichi, and the recast was so long that they ended without shadows frequently.
So, what did groups do ? Bring two NIN. This way, they could manage their enmity to swap when needed thus ensuring enough mitigation.
And since NIN were designed to be DPS from the get go, you didn't lose any DPS by bringing two NINs instead of a PLD with an additionnal DPS.
So, on really tough bosses, not all tanks would be able to be MT 100% of the time, but any combination could do the content. That's why I suggested on another topic to slightly reduce WAR's mitigation (To be clear, just giving them back the old Inner Beast while keeping other skills as their are now).
BUT, as a counterpart, fusing Wrath and Abandon and giving WAR full acces to Wrath/Abandon skills regardless of their stance.
