I think you are probably right that most aren't proposing changing the actual protocol. However, I think part of what the post is reacting to is the marketing a

I think you are probably right that most aren't proposing changing the actual protocol. However, I think part of what the post is reacting to is the marketing around the ideas for new clients, or the perceived need for new clients. I haven't been following this so closely, but the articles I have read seem to position these proposals as changes to e-mail as a system, if not as a protocol. I leave thinking the authors want to do something radical, to alter something longstanding, to go up against giant, ingrained players and conventions. I don't think this post would have happened if we were instead hearing more about "new ways to use e-mail," or "adding functionality to an email client." I think the narrative is more like, as others in the thread have referenced, PG's frighteningly ambitious ideas, more like visionaries who are daring to challenge something so established. Making a new email client that has some extra features is one thing. Changing email forever is another. I think that's what the post is reacting to. Edit: and, anyway, I think sharpening the discussion by invoking the difference between the client and the protocol is useful, and hopefully will make future conversations about this more clear.