The user name is their radio callsign, which you can look up in the FCC database. I don't know how much more attachment to a "real-world identity" you're looking for.
Now, most of the work done with radio telescopes are passive, but they are really just large dishes capable of receiving any radio signal, including ham stuff.
Often Amateur Radio websites are functional at low bandwidth as the hobby is in some way designed for use when the main systems fail.
Still a lot of truth to your comment.
POP3 is supported, by the way, I just didn't list it. That's my fault https://docs.mailcow.email/client/client-manual/
Kudos on POP3 support. I never liked IMAP as I've always preferred to keep my emails between the server and client stored independently. Call me old fashioned, albeit in a different vector from hams.
If there's anything I found to be common of all the ham operators I've met or heard of, it's that they're all electrical engineers at heart with not a single fuck in the world available for form or aesthetics. Jank and old-fashioned are their pride and passion.
Source: Father is ham operator, has the time of his life janking it up with his ham friends who likewise jank it up.
P.S. Not supporting POP3 is asinine.