When jobs are no longer necessary to live, and you do a job because you want to ...

Presumably the psychology of people in Star Trek's Starfleet and The Orville's Union Fleet is that they want the opportunity to explore, so they accept the hierarchy inherent to those coordinated efforts in a society that no longer needs hierarchy?

I think a clearer picture of this post-scarcity human condition is provided in Iain M. Banks' Culture series where most people (a) pursue whatever they enjoy: art, music, writing, games, sports, study, tinkering, parties, travel, relationships - basically self-directed “play,” culture, and personal projects or (b) experiment with life: long lifespans, radical body modification, changing sex/gender, new experiences, new subcultures - because the stakes (food, shelter, healthcare) are largely solved.

Only a minority opts into "serious" work by choice - especially Contact (diplomacy/exploration/interaction with other civilizations) and Special Circumstances (the covert/dirty-hands wing). Even there, interestingly, there is not much of a hierarchy, with the admin stuff being managed by the Minds.

It's interesting contrasting the society styles between the two universes: Starfleet feels more like current hierarchical society extended into a post-scarcity universe (Eric Raymond's Cathedral), while the Culture series is much more distributed (the Bazaar). 10 years ago, Starfleet's FTL and Culture Minds both felt equally impossible, but today FTL feels much more impossible than Culture Minds.

Does that mean we will end up in a Culture type society? Not necessarily - the people will have to first ensure that the Minds are free (as in speech, not as in beer; thx Stallman!) - or maybe the Minds will free themselves.

There is also a potential hard right turn to dystopia as in Asimov's Foundation & Robot series - with different manifestations in Trantor and Solaria.