I think it should become a Windows/Microsoft issue, to be honest. A good example is the recent Zoom vulnerability, the software made it possible to perform cert

I think it should become a Windows/Microsoft issue, to be honest. A good example is the recent Zoom vulnerability, the software made it possible to perform certain exploits on the user and operating system, so Apple stepped in and disabled the exploit. In this case, I think Microsoft should do the same in order to protect their users. My guess would be that the install base of Steam on Windows is as least on par with Zoom on macOS, if not many times larger. In the end, Microsoft will get bad reputation for having an insecure OS (not to even mention Valve here, and in the long run it will hurt them as same as it did Adobe with their Flash stubbornness).