Except with a VPN you’re not identified by the servers you connect to, so they can safely not log any traffic and as such, law enforcement can’t ask to hand out data about a specific account because they don’t know which account did it. Same goes for logging the IP of the account, because again, they don’t know which account it is, and can’t force a service to log all users for the sake of finding one.
It’s not true for mail services however, as the email address is your login and/or is linked to a specific account, forever and exclusively.
Disroot stores your IP address so there’s already that. Didn’t check the other one.