Thing with email is that you'd also have to get everyone you talk to to move to it and ensure they don't fall back to any of the services they have been using f

Thing with email is that you'd also have to get everyone you talk to to move to it and ensure they don't fall back to any of the services they have been using for all this time for convenience's sake. At which point, it doesn't even matter if it is email behind the scenes or something else. There's also the issue of SMTP being very metadata heavy and there being no option to mitigate or encrypt any of the metadata. Which is why something like Delta Chat (if you haven't heard of it, it's basically Signal/WhatsApp like IM piggybacking over email) isn't very private.