No, they give you IMAP capabilities; it's up to the client to build something more intelligent on top of that -- tagging and snoozing are totally compatible wit

No, they give you IMAP capabilities; it's up to the client to build something more intelligent on top of that -- tagging and snoozing are totally compatible with IMAP as long as the client does something intelligent (it doesn't even have to be extremely non-standard; IMAP keywords and mailboxes can do the job perfectly here). Your mail client doesn't have to be a 1-1 mapping to IMAP commands, like pretty much all mail clients are. This problem is the same as GPG. Why is GPG not more widespread ? It is widely accepted that the technical parts may be old but are still solid, the real problem is the UI. It is still immensely difficult to create your own keychain and share your keys with someone else. Only in the latest versions does gpg introduce TOFU. It has always been a UI problem, and will remain this way until someone wants to tackle it... or replaces gpg.