It's email that gets to reinvent ~30 years of formal and informal specs and interoperability hacks because it controls all clients, and all servers in between.

It's email that gets to reinvent ~30 years of formal and informal specs and interoperability hacks because it controls all clients, and all servers in between. And yes, there's a lot wrong with email, it's just that it's familiar and we've figured out how to work around/live with a lot of the badness.