Well, it’s a list of "well maintained/moderated servers
Any server that federates with threads, a product of Meta a company known for their low quality moderation and lack of ethics, is clearly not a well maintained/moderated one.
It’s not a new rule. The admin is just applying the sites rules as they are, instead of making exception for threads as many of the techbro admins that are getting their servers excluded have been doing.
Why would I want to follow either account?