we owe it to the users of instances we block to announce we're doing so _and why_ so that they can choose to move instances if they lose access to their friends/contacts
no we don't owe them that access - it's fine to block/silence instances over moderation decisions, assuming good faith &c - but we do owe them the knowledge of why they are losing that access, especially if it's not their fault.
btyb a cybre.space user who has no idea what the heck is going on atm