Comment by mdaniel

Because it's only INSERT not SELECT nor DELETE? Maybe you meant IMAP which does have APPEND <https://www.rfc-editor.org/rfc/rfc3501.html#section-6.3.11> to insert a new message into a folder, and a bazillion SELECT options, plus of course DELETE

I still would call that crazy, because of the mental tax of explaining to every new employee "wait, you're using IMAP for what?" but if it works for you, then great