It is the aesthetic of seriousness and moderation they crave, the ability to look and seem professional and educated independent of any substantive proof that they are. This fakery is unveiled whenever you see a Celebrity Jeopardy episode where the news anchors/political commentators get demolished by comedians, even though the anchors appear way more put together and well read than the comedians do.
A lot of the Ivy grad pmc centrists don't know shit about shit, they just know the style choices, catchphrases, and speaking cadences that will get them clocked as thoughtful and competent by the layperson, while letting them ward off questions from smart people that actually probe their depth of knowledge.