@nprofile1q... As for keeping your privacy…
Mullvad sells (tamper-proof) paper vouchers on Amazon.
I buy one with my credit card. Amazon ships it to me. They know I bought a Mullvad subscription. But they don’t know which account it relates to.
Mullvad knows they shipped a bunch of paper vouchers to Amazon. They know this voucher came from there. But they don’t know who I am.
This seems a simple method of firewalling the purchase information from the service to which it relates. Given Proton’s size, and its professed security credentials, it’s curious why they don’t do similar.