But that’s exactly my point. Sign-ups to lemmy.one were always closed so you needed approval from the admin(Jonah) to create an account on the instance. Now since Jonah is not actively involved, nobody can join lemmy.one because he is not approving their accounts anymore. So no new person can join the instance.

As for the users already using a lemmy.one account, they have been using the fediverse peacefully without spamming anybody, even during the past 2 months when jonah was not active. In fact this seems to be one of the best behaved instances. Now maybe there is a sleeper agent among us lemmy.one users who was waiting for Jonah to become inactive before starting their spamming activities but somehow I seriously doubt that.

Considering the points I laid out above, I feel that the defederation was an unnecessary action taken by the lemmy.world admins. The risk of spam is very miniscule and this small risk does not call for the use a nuclear option like defederation.