This is not new.

Jobs that buff other jobs have always traded off personal DPS to compensate. Ninja has lower pDPS to compensate for Trick Attack, same for Bard and Machinist pre-ShB. Dancer is exactly the same. Black Mage, on the other hand, provides so little utility so to compensate it has lots of pDPS.
There might be balancing in the future to Dancer's potency values but don't expect to be doing BLM levels of damage on a job that can buff everyone else's damage.