We’d all like Steam to be open source, but that’s not going to happen for a number of reasons
We should fight to make that happen or at least not pretend that it's fine.
We like Valve because they are actually contributing to open source projects, unlike Microsoft who say they love open source but don’t do anything to support it.
I don't deny their contributions. We should praise them for the good work that they are doing, but at the same time we should criticize their bad behavior. Microsoft makes Free Software too (VS Code kinda, TypeScript) and they give money to the Linux Foundation. But they also do a lot of unethical things.