That's a bit harsh given all the problems SMTP and IMAP have. They are very dated and have some exotic "features". There is not a single mail client that gets everything right!
Well, no shit, they were designed before HTML and HTTP, not just JavaScript, and there’s zero need to actually shove them into that mold because they already exist and are fine as they are in terms of protocol-level features. If you can’t deal with that maybe you shouldn’t be trying to do development at that level.
Meanwhile, all that energy spent reinventing the protocol layer to be maximally aesthetic to people for whom all the world is JavaScript running in a browser could have been used to actually improve the applications running over the protocol.
The words "they", "are", "very" and "dated" are even older, so don't use them if you want to be hip.