I typed a long response but it seems to have disappeared.

It wouldn't be hard for Reddit to find sympathetic mods to jump in. Any mods of big subs that didn't participate in the blackout would likely be thrilled to grow their empires.

If necessary, Reddit could throw some interns or some contract employees at the problem. A huge part of the job moderating the giant subs is removing spam and other obvious rule violations. It doesn't take specialized training to check a report to see if it is accurate and click ban/remove/approve.

The parts of moderating a sub that do take special skill -- the parts related to growing and tending a community through thoughtful application of subreddit specific rules and norms -- will not be missed in the million+ subscriber subreddits in the short-to-mid term. r/funny and r/TikTokCringe and whatever other giant subs don't really have any quality standards to speak of anyway.