Proton requires an account, which gives them some of your info, while Mullvad does not, giving you an anonymous account number instead.
If Proton really doesn’t log VPN traffic, then it doesn’t really matter. But since Mullvad does not have that same personal info, they would be unable to provide law enforcement or 3rd party data brokers any hard data aside from your IP if they wanted to.
Proton requires an account, which gives them some of your info, while Mullvad does not, giving you an anonymous account number instead.
If Proton really doesn’t log VPN traffic, then it doesn’t really matter. But since Mullvad does not have that same personal info, they would be unable to provide law enforcement or 3rd party data brokers any hard data aside from your IP if they wanted to.