Further downhill than secretly installing an IMAP proxy on your phone and hijacking all your email to go through it in a way that destroyed all TLS security to your real mail server? Impressive...
Though, I was thinking that same sort of technology might come in handy for people that wanted to have encrypted email, without having to use a special encrypted email app: proxy through an app that did the encryption and decryption, but didn't store anything.
Yeah [1], and that's not even mentioning that the motivation behind those questionable "engineering" decisions was to be able to read and modify all your emails, helpfully injecting linkedin content into them.