It would be a super interesting case study if two (or more) sizable communities on different instances dedicated to the same topic decided to all consolidate. It’s hard to imagine that happening without some unplanned change - like most of the mods of one no longer being able to put the time on anymore, and not enough “local” users willing to step up?

I think the best Reddit blackout trackers are the ones that highlight the most popular subreddits, like this one showing 204 of the top 250 are dark: https://save3rdpartyapps.com/