error loading post text
A related question I have had is: can you transfer communities you have created to another instance? I'm sure the answer is no.
I've been very happy with lemmy.world, but I will be stopping my donations and finding another instance if it federates with Threads.
error loading comment
Nothing. They will exist as long as the instance exists.
You can appoint a new mod yourself before leaving, or your own account from a different instance. But if you are the only mod when you delete the account then yes. Instance admins can still apoint someone else though.
Technically, there's instance admins. But I don't know.
Permanently Deleted
I am sure.
They will likely disappear.