So if you're using Proton thinking it's "privacy-focused", it turns out they're giving data to the Feebs now. https://www.404media.co/proton-mail-helped-fbi-unmask-anonymous-stop-cop-city-protestor/
Proton Mail Helped FBI Unmask Anonymous ‘Stop Cop City’ Protester

A court record reviewed by 404 Media shows privacy-focused email provider Proton Mail handed over payment data related to a Stop Cop City email account to the Swiss government, which handed it to the FBI.

404 Media
@adrienne fuuuuu....
What is the alternative? Just roll my own? Fucking hell...
@smolbrain
Maybe an other alternative for a classic and secure provider is mailbox.org . You can encrypt your entire mailbox there, including incoming emails automatically. If necessary, you can keep the private key yourself.
https://kb.mailbox.org/en/en/business/encryption/the-encrypted-mailbox-encrypt-incoming-emails/
mailbox.org is in the fediverse: @mailbox_org
and here is the homepage:
https://mailbox.org
@adrienne
The encrypted mailbox – Encrypt incoming emails | Knowledge Base: Knowledge and help | mailbox

Activating Mailbox Encryption

@werawelt @smolbrain @mailbox_org @adrienne Mailbox has the same vulnerability. It's a legal, above board operation and will also respond to court orders to hand over metadata they have for the account.

The solution is not to trust any of these companies if you need anonymity. Pay them with cash instead of a credit card, don't setup a recovery phone number, and always use a good vpn or Tor to connect. They can't hand over what they don't have.