It's extremely difficult to accurately identify which emails have health info and which ones don't (even something like a person's name or IP address could count depending on the context) so they just default to sending everything through their message center. No amount of email security could change that.
I'm sure there's a sum of compliance reasons why this is not allowed, but it doesn't make any sense at all.
As such, I tell anyone who sends me one to fuck off and send a real email.
And then also sends an e-mail, which sometimes I confuse and think is ANOTHER message, and log in again....
It has a "Download this message as a PDF" button, which just takes you to a web-browser wrapper....
This will literally never happen. Email doesn't support the features that those messaging platforms need to have, such as recalling messages.
The security layers are also only on the sender part, not on the receiver part, which banks care a lot more about.