Yeah that's really such a problem as well. I don't see how you can do something right now without crossposting to death in all those places, which must make it even more exhausting. I remember the same thing happening back when LJ fell apart. I'd fallen out of fandom at the time, and it took almost a decade to find where everyone else had moved to. Advertising on Discords is probably something you can do too, but maybe you can bring on a mod just for crossposting? Part of it has to be choosing a platform and sticking with it for updates as a primary comm, if people are interested in it they'll go there (like with the spn reverse bang on LJ). I agree it's not great though and I wouldn't want to be running or even joining another bang or bingo at the moment (I already missed the Pinefest deadline)

I've had problems getting any information out at all, and to my surprise there's more activity and conversation here than in my tumblr (apart from reblogs of old content which seem to be going full swing just like it's a normal week) and definitely more investment here than on pillowfort.