@AndreasThinks I suspect this is a reflection of the specialized nature of those topics--they're a bit unapproachable to amateurs--which means the population of potential people to participate in those conversations is a bit small.
And it just happens to not have much overlap with the Fediverse userbase, as workers in the field also just might not have that much free time to dip their toes here and sort through all of the other topics that do get more airtime here.
Maybe ironically, better AI would help make Fediverse feeds more useful to people like them, as the chronological sort is unwieldy.