its likely that most moderators, certainly the so called super-mods, are paid staff. The vast majority of people don't have the time or inclination to do that kind of thing, certainly not without renumeration. I imagine there are exceptions, obsessives or hobbyists or idealogues, but even then such people need to have the time to do this kind of thing, which means they're certainly not coming from the bottom of the pyramid nationally or globally. With the structure of that site being what it is - silos of information/contribution policed by anonymous accounts - it looks to me a lot like an informational warfare experiment, one big psyop.

targeting the demographics it does - originally and most notably tech workers, but broadly the PMC - makes sense because they have skills and educations and a place in the hierarchy that make them somewhat useful/dangerous to a state. Like they target academics, not via that site of course but in other ways.

edit; I forgot to mention another common category of user/poster/moderator, the grifter. The merchants and artists and scammers looking to promote their brand/show/product etc and sometimes denigrate that of their rivals. This is more difficult on reddit because of the relative anonymity but wherever people gather the vultures circle too.