Mudra why so many ninja don't use them?

[Espon]

I haven't seen too many ninjas not using mudras. What I do see too much of is Doton on single-target bosses. Raiton does more damage instantly than Doton's entire duration, is faster to cast, and allows you to use Raiju.

If players are ignoring important parts of their kit, that's more often a problem with the player and not with job design.

[Jeeqbit]

What I do see too much of is Doton on single-target bosses.

That's because it used to be slightly better to use it on a single target (I think by a single DoT tick). It seems that SE fixed that oversight.

i was confused what my tank stance did i kept spamming it off and on like a random cooldown

I've seen tanks do that occasionally. Rare, but amongst my thousands of dungeon runs, I've seen it multiple times.

[Rithy255]

I've seen tanks do that occasionally. Rare, but amongst my thousands of dungeon runs, I've seen it multiple times.

I think this is because tank stances are pretty confusing, most people aren't going to know what enmity means, but yeah I've seen it a couple of times myself... But i've seen things like level 90 Gladitors so I'm used to seeing wild things in ff14.