I've seen some post that FOSS dev worked for Valve as contractor. It's great that my payment for games finally go for FOSS developers and they develop FOSS. Also they expand real world usage of GNU/Linux (Linux Desktop!). https://news.ycombinator.com/item?id=35605865
I wasn't a big fan of Steam so I've bought games from random store, but I'll buy any games from Steam as possible.
Apparently lead graphics developer of Asahi Linux works also for Valve now [1]. If you have followed her work, such a talent.
[1]: https://rosenzweig.io/resume.pdf