Confusion Mounts Over Wayland's Actual License
It turns out, Wayland's code license may have been slightly incorrect all these years and doesn't comply with the FSF / open-source definition.
A Wikipedia editor of technical articles pointed out that the FAQ on Wayland's FreeDesktop.org site says that Wayland is MIT-licensed. However, the actual license text within the Git tree uses the Historical Permission Notice and Disclaimer (HPND) license.
The HPND is used but it's been deprecated upstream by its authors. The HPND wording also hasn't been declared a Free Software license / GPL-compatible by the Free Software Foundation, though it technically shouldn't see any objections. Further HPND information on Wikipedia.
This message finally led Kristian Høgsberg to reappear on the mailing list. Kristian started the Wayland and Weston projects but he hasn't been actively involved in Wayland for about a year. Kristian commented, "Yes, it appears you're correct. The HPND license is widely used in X and I think I assumed it was the most recent/modern version of the MIT license. It was certainly the intention to change the license to MIT and that's what all contributors acknowledged when we relicensed. Let's wait a few days and see if anybody objects, but otherwise I think it'd be fine to just change the Wayland and Weston licenses to the actual MIT license."
This license snafu could also have broader implications as Libinput is effectively forked from Weston code.
From the developers commenting thus far, they all expressed they're okay with the license text being changed to the proper MIT license, but I'll keep following the mailing list thread and post an update if anything else developers.