@SolSoCoG I think temporarily muting repeatedly offending instances is unavoidable.
My two cents on this is:
This shouldn’t result in a permanent suspension of an instance unless the spamming issue persists on a subset of instances
Solely relying on user reporting spam is not good enough. If a user received 2 spam messages, they will likely report them all. But if a user received 2000 spam messages in a day, it’s not realistic to expect anyone to report them all.