People are often quite vague with their use of the word 'utility'. At the end of the day, the primary thing that teams care about is rdps, because that universally decides the outcome of fights. Offensive 'utility' is included in this, as rdps factors in the dps gain provided by the buffs that you bring to the table.

Defensive utility has situational value, especially during early progression, but is fundamentally less important. And some forms of defensive utility are just better than others. Being able to raise a party member to get more exposure to later parts of a fight can be great. A bit of extra personal or raidwide mitigation might help you survive a dicey situation. But this isn't ARR T13 prog where you're bringing double MNK for Dragon Kick INT down.

It's an apples and oranges comparison. You cannot scupper a job's dps compared to other jobs that share a raid slot simply because it happens to have something that you've classified as situational defensive 'utility'. You have to balance rdps with rdps, and defensive utility with defensive utility if that's really a problem at all. But claiming that a 50 potency regen justifies the dps disparity that currently exists is just a bad argument. And if it really balanced out, you'd be asking for the utility, not to keep the dps advantage.