They do have e2e for emails. Any emails between Proton Mail users are always e2e encrypted, as are any emails others send you which they’ve encrypted with their own maio client. If someone sends you an email unecrypted (most email is), then Proton will encrypt it for you and put it in your inbox. They can’t read it after that, but there is some trust required that they don’t store/look at the unecrypted email before then.

She’ll independently recycle your matter into more coffee.

It’s been a while since I’ve had to touch it too. But couldn’t Alice provide Charlie with both the plain text and her public key. Charlie could then encrypt the text and see it came out the same as blob Bob sent Alice?

Typically end to end encryption includes digital signing of the message so you can verify who the sender was.

Yeah, end to end encryption means its not possible for someone to intercept the message between person A and person B. Nothing stops person B then forwarding the message to person C to report it.

I quit more than a decade ago now. I still occasionally get a craving for one. I don’t get the same physically reactions that you listed. Mostly get the cravings when I’m stressed.