The steam client is only officially supported on Ubuntu and only using KDE, Gnome or Unity.
No. They offer a .deb package but repackaging and redistribution is allowed.
Valve’s support team won’t check issues on any other Linux setup.
That’s false. I guess you never actually reported a bug on their Github page. Here is a random bug report from Steam on Fedora installed from RPMFusion with a Valve developer asking for details instead of closing the issue for being unsupported: https://github.com/ValveSoftware/steam-for-linux/issues/12422
Steam web and the readme in the repo says Ubuntu is a requirement, so they are not being very clear on what they do give support to. I know they allow redistributing the client, but that is a different thing.
No. They offer a .deb package but repackaging and redistribution is allowed.
That’s false. I guess you never actually reported a bug on their Github page. Here is a random bug report from Steam on Fedora installed from RPMFusion with a Valve developer asking for details instead of closing the issue for being unsupported: https://github.com/ValveSoftware/steam-for-linux/issues/12422
Steam web and the readme in the repo says Ubuntu is a requirement, so they are not being very clear on what they do give support to. I know they allow redistributing the client, but that is a different thing.