[mildred593]

JMAP really solves many problems and allows you to do many things that are just not possible with IMAP. Also, IMAP has many ways to (badly) perform the same task, not all supported by all servers or all clients. MIME parsing is not easy to do and there is not always quality libraries available for your language... JMAP solves all of this.

[kazinator]

JMAP doesn't solve any problems that I have. That's because I'm not a monolithic mail company trying to take a slice out of Gmail's pie.