Historically, the unit used to tank depends on what it has to defend against.

- A sword: a shield or a blade composed of a guard and a hook.
- a rider: a spear
- archers against a foot or horse charge
etc.

But let's come back to FFXIV...

The image I have of a tank is a heavy armor with a sword and a shield, so the PLD. Except that it sucks at ShB by its gameplay.

Don't like the GNB style that only speaks to Squall Leonhart fan, FFVIII is my favorite FF, but a guy in a furry jacket and a T-Shirt, that doesn't make a tank. And its gameplay with ammo doesn't make me think of a tank : Wait I reload and then I start again.
Even though, blah, blah, blah. Mostly, I don't like his gameplay.

WAR is a berserker in armor, a berserker historically is a guy in leather armor, often represented shirtless. And it's more of a 'glass cannon' than a tank.
For the gameplay, it seems slow to me and the axe as a weapon does not speak to me.

So my next tank after PLD is by default a DRK, not because it's too dark.

It would be nice to have a tank with a shield and a spear, too.

Understand that my point of view is more historical than Japanese heroic fantasy, where the tank could be a woman in a leather or plate bikini jumping around at the speed of sound.

Tanks with naked swords and shields or in T-Shirts don't work in real life, your attacker is not going to aim just at your sword and shield, to please you.