Came here to follow up with this.

I don’t care what magic beans my email provider wants to sell, at the end of the day they’re only able to do encryption within their own server which is pointless.

Anyone who thinks email is not immediately plain-text when they hit the send button (because, frankly, it is) is suffering from some weird marketing-induced delusion, or just plain doesn’t understand that proton encrypting something, or SSL in transit is not going to do a single damn thing to improve security.

Sure my copy of an email is all nice and secure, but the other copy of it almost certainly not, unless you use something like GPG to force the contents to be transmitted encrypted, and fucking nobody uses GPG outside of very limited situations.