> I dunno if I'd characterize this as "public"

Then define public and state what's wrong with this repo which conflicts from your definition of public.

For me this looks like a fine public resource and after a short glimpse it looks like that you should be able to even build this effing source code from this repo.

Edit ps. If you edit your own content then please leave a note about what you have changed please

The linked repo isn't the official public resource. Valve provides the source packages for what they distribute (aka GPL compliance) but this person wanted them to open up their private GitLab instance to the world.

As far as I can tell, they wrote a script to download the source packages they provide and then try to reconstruct them into a GitLab repo.

Well based on the paragraphs in the README it's not actually being updated anymore, it only reflects SteamOS as of August and the author quit running their process to update it.

The ask was "when are we going to get a public release for SteamOS"

Someone's bootleg copy of the private repo is not proof that it has