I agree with everything you're saying (though my favorite is probably addresses containing newlines). My point is just that in practice it's not terribly useful

I agree with everything you're saying (though my favorite is probably addresses containing newlines). My point is just that in practice it's not terribly useful, e.g. why HTML5 defines its own: https://html.spec.whatwg.org/multipage/input.html#valid-e-mail-address https://html.spec.whatwg.org/multipage/input.html#valid-e-ma....