If it's possible someone can come up with a small UI that only lists and launches games.

Playnite [1]. Open source, lightning fast, and light on resources. You can even combine different platforms such as Steam + Battle.net. Saves you running each of these. Though you lose things like downloads and social. Heck, it even has support for emulators.

[1] https://playnite.link

From the article: https://github.com/DioJoestar/SteamCMD-GUI/blob/master/READM...

They don’t seem to have a *nix referral, but seems totally possible to make.