I suspect that multiple people will create multiple subs on multiple servers with the same topic (movies / TV / NFL / Formula 1 etc), but over time one will become the definitive one and people will migrate to that and the others will either shut down or maintain a low user base.

Are you asking me? I'm not sure because the buttons to answer a thread or a post look the same in the jerboa app and I nearly made the mistake to answer a post instead of a thread already.

As far as I understand it works like this: you don't need to set up a whole server. You can add a community on whatever server you like. You will automatically be a mod then. I'm not sure if it's wise to search for random co-mods right now though, because the whole community will get a boost now and there will be tons of people where you can't estimate their reputation, so it might be vulnerable to bad actors atm.

I'm starting mycology subs (mags?) Right now over at kbin and I think I'll look for co-mods in a few weeks, after the dust of the migration settles.

Just do it. Commitment will make the whole thing thrive!