It's a stark contrast to Tuta, which allows anonymous account creation with Tor Browser if you pay with cryptocurrency (Monero or Bitcoin, via their partner ProxyStore) and doesn't require a whitelisted verification email address or any other data.
An additional email address is required only in cases when our system detects something suspicious about your network, so if you are coming across this, we recommend changing nodes. If you keep coming across the same issue, please contact us at: https://proton.me/support/contact, so we can take a closer look.
The email addresses, however, are not tied to your account - we only save a cryptographic hash of your email address. Due to the hash functions being one-way, we cannot derive your data back from the hash: https://proton.me/support/human-verification.
Who cares if you hash it, cracking a hash of an e-mail is easy AF compared to passwords. Especially on agency scale... How do you hash it? Argon2 or rather some extremely fast to crack hash?
It's a difficult issue. If they allow unlimited signups via Tor, people will bulk sign up for accounts and use them for spamming, scamming, threats, phishing and other crap. I can imagine why they don't tbh.
Proton forbidding anons from opening free accounts might be necessary for anti-spam/deliverability. But even paid accounts?
"They accept cryptocurrency, but only for existing accounts - after you've already doxxed yourself" (during the initial signup flow, where this payment option has been removed)
You don't doxx yourself by creating a Free account. In most cases, no human verification method is required or it's captcha only. As explained above, an additional email address would be required only in cases when our system detects something suspicious about your network.
It takes a while for the Bitcoin transaction to come through, which is why we the process is the way it is. The same process applies to users who wish to pay with cash or bank transfer.