Bard used to be a very bad job in endwalker until it was buffed in DT by adding massive CC potential and damage, thus now it's no more of a joke job.
DNC used to be bad in endwalker but then JP players started to spam it massively, got popular, got buffed and ever since it has became a problem for CC meta.

DNC main issue is that it relies too much on your teammates. Having a premade (someone you know who appears into your game) makes the chances of winning much higher. Dance partner with tank such as GNB and you are set to win. DNC also shines pretty well if it is in a team with Dragoon, GNB, Warrior or any similar that can perform tons of damage while dancer occupies every player with its lb. It's a disgusting thing to say the least. DNC can also use its LB to make people die in clock tower (unless that was fixed, I don't know).

It's definitely one of the most annoying classes out there solely because your LB dictates how everyone plays around it and thus why this class will be always hated by everyone.