To support decentralization and spread, should lemmy.world close registration at some point to prevent a performance overload due to too many users? Of course, if registration is disabled, there could be a hint placed somewhere near that from other instances you can interact with content on lemmy.world just like you had registered on it. There could be a link to join-lemmys instance overview.
It’s already laggy and unstable. Maybe more hardware and improved software will help, but it might just be hard for lemmy to grow.
It’s not hard for Lemmy to grow at all. Use a different server. There’s no upside to being on a crowded server. Join a fast and reliable server. Hit “all.” Done.
Lemmy is designed to grow easily.