Especially because discussing copies of your own data also happens in such communities. There must be clear guidelines what can and cannot be discussed. Also, it would have been nice to have those communities selfregulate. For example, giving them 30 days to comply, e.g. removing any content that breaks the law.
Because the fediverse i about democracy. If laws stand in the way of democracy since they have been brought up by governments influenced by global corporations (which are by definition autocratic) then they must be ignored.
So, striking a balance to not get anyone in trouble while not working for IP holders is the way.