It seems like concept of threading is too complicated for average user these days. All the new & trendy software for communication have no threading capabilities -- Discourse, Google+, Github issues, Moot.

Threading is good for reading through one time and when there are many topics of interest. Email is something you often return to again and again and topics are organised using subject headers. Email discussion view was introduced by google a very long time ago before almost anyone else did it. It is a bit of a cosmetic trick where it just sorts emails that have the same subject. Threading does not jive with the way Email technology is structured.

Remember when Google tried to build a brand new huge piece of technology meant to revolutionise communication on the web? Nobody adopted it, was called Wave.

How exactly does threading ‘not jive with the way Email technology is structured’? In-Reply-To: and/or References: are pretty much all you need for threading.

Reddit is bigger than all of those, combined :)

And Facebook added threaded comments recently too

At least we still have sane threading here at HN.

I agree; that's one thing that I notice, especially in an email chain with a lot of people in it. What would you like to see Gmail do about it?

Indenting and maybe vertical lines to help the reader figure out the threading would be an improvement. However, I don't think this is good enough in a long email chain. The way traditional email readers solve this is, of course, is with two views, one of threaded email subject and another for contents (http://www.davep.org/mutt/screenshots/). I don't think gmail will ever adopt this interface, though.

agree