[tallanvor]

I honestly can't see this being something that would ever result in enforcement action.

They have a legitimate business interest in not spamming someone if people try to sign you up multiple times, and since the email address is hashed, all they can use it for is to determine if they've sent you an invite before (and potentially when they did so, or when you declined the invitation).

Maybe they could get in trouble if they also retain information on who is trying to send you invites and creating a graph and a shadow profile based on this type of information, but it sounds pretty clear that this isn't something they're doing or are interested in doing.