That being said good filtering, threading, and end-to-end encryption in one reader is still illusive for most of us.
Email doesn't fit the way a large number of people think, but I don't think it's broken. Neither Excel nor Windows is inherently broken just because I have issues using it, I just need the proper training.
Some people have 10GB of email in their inbox, because then: "they know where it is". Some mix work and private emails, because then they don't need two email account, which is just awesome when they chance jobs. Then there's the people who just have plain bad communication skills and can't formulate a clear and readable email. Neither of these things point to email being broken and I have yet to see a half decent alternative.
I love email too, but way to many people aren't correctly educated in using it.
I don't really see what is the problem with that sort of pattern?
I think it extremely disrespectful to send a email and two minutes later be standing at my desk ask: "Did you see my email?" No, of cause I didn't see your email, I'm working.