Earlier quoted context omitted.
This has been my experience. The only "good" experience I've had with encrypted messages through email was a back and forth exchange I had with a fellow Keybase user where I manually copy and pasted blocks of encrypted text into/out of their web interface.
From my experience - the only PGP users I've spoken to were all on Keybase or interested in a Keybase invite. It was about 6 people for the entirety of last year - and 3 people this year...it certainly has a problem of "almost nobody uses it" but Keybase seems to have eased things slightly - or at least made it easier to discover people who also use PGP. I see the two problems being "People don't bother with the clun…
Additionally, and I realize this is tangential to this discussion, I use pseudonyms to somewhat reduce my privacy "surface", so to speak. If I take my twitter, HN, reddit, etc, etc. and say "this is me", you could build a pretty decent profile of who I am (politics, hobbies, profession, where I live and so on). That's a different privacy problem than keybase is trying to solve, so no criticism is intended, but it is a problem for me.