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.
I think strategic, times windows where sign ups are paused, in order to help distribute users, might be necessary. I don’t think that’s optimal for user experience, but I feel like if volume of sign ups stays where it is, that it’s probably needed.