I think it has more to do with the fact that MCH and DNC are...boring. Yes, sorry, that's what they are. BRD is the only one that has a modicum of complexity and fun in it.
They should probably focus more on giving them a more interesting gameplay loop. But yeah, given the current situation, some potency buffs are clearly needed for both MCH and DNC. It's not going to change much in terms of job popularity, I feel.