Almost! At the time of this post, lemmy.world has a whopping 25733 users and is growing fast.
Since my last post yesterday, it has added 4000 new users, making it the clear second-largest lemmy instance out there. Also quickly catching up to lemmy.ml's 36000 (not taking new signups).
beehaw.org (3rd largest) sits at 12500 users, partly because of more restrictive registration requirements.
Source: https://lemmy.fediverse.observer/list
Exciting to see all this growth!
There is an advantage that Lemmy's backend is entirely an API with a detached frontend. There are already API wrappers for Rust and Typescript that are officially supported, so I'm sure it's only a matter of time before someone writes a robust automod that can be implemented for communities that desire one.
I have a bit of interest in doing it, but I know nothing about the API itself, so I'm not sure how easy it would be to grab every new thing submitted to a community or instance for moderation.