I was not implying to permanently remove them. I did indeed mean to remove them while they're defederated. They said they can't handle the influx of users with only 4 admins.
Obviously they would be readded when they refederated.
Also, isn't that just what the de/federation system does? Instances can decide on their own, we don't have to agree as a whole. Who owns 'lemmy proper' to make the call which instances are displayed on join-lemmy.org or removed from it?
But what definitely should be removed is this line:
You can access all content in the lemmyverse from any server/instance.
That's simply not true, and creates false expectations. Either change that line or only show instances with 0 defederations.