Are IP addresses really helpful in moderation? Moderation usually pertains to the content itself, meaning you would want to block certain content from being posted regardless of the IP that sends a request. Maybe you extend moderation to include banning users, but at that point you have more specific data than IP addresses (like usernames or user IDs).

You can target a list of suspected spammer IPs, though that's often a losing game of cat and mouse where you end up missing some spammers and catching legitimate users in the crossfire.

I know that for Instagram/Threads, IP is very key to their moderation. Once they ban a user with that IP, any other account from that IP will also be banned (or something like it), it's fundamental to avoid ban evasion.

For Mastodon, all of this is manual, so it will be up to moderators on the server....