HURD can largely be regarded as a cruel joke. It's been under development for over twenty years (since 1990!) without yet producing a usable product. Pretty much every operating system kernel that's in use today (Linux, the BSD family, Windows NT, and XNU) is younger than HURD, and yet far more mature.

If you are measuring the current hurd kernel's age as starting from 1990, then the BSD kernels are far older, not younger. The initial release was in 1977, and obviously development started before that.

That said, hurd is essentially abandoned at this point. Even RMS has accepted that it will never be completed, and has said that it really doesn't matter since there's already a free kernel available (linux).

"Get Xorg + gnome/kde/xfce (xfce should work, kde is missing working dbus (due to local socket auth and bugs in select() cornercases)) + some webbrowser working (iceweasel 9 works, though not https)."

From GNU/Hurd TODO list :)

  bugs in select() cornercases

is the thing that stands out to me. Seems like I would want select() to be pretty solid to consider this a viable alternative.