Just getting this up here; I'll update it and add links as I have time.
Proton (https://proton.me/)
Purelymail (https://purelymail.com/)
Tuta (https://tuta.com/secure-email)
Fastmail (https://www.fastmail.com/)
Mailfence (https://mailfence.com/)
Mailbox (https://mailbox.org/en/)
Some other resources for email:
Migadu email (https://www.migadu.com/)
Privacy guide for email (https://www.privacyguides.org/en/email/)
Privacy Pack - this offers alternatives to commonly used big-tech apps (https://privacypack.org/create)
