Absolutely not. Game developers have deep deep knowledge in making games for Windows and PlayStation type OS’+hardware. Studios aren’t going to spend years having their devs relearn nuances specific to Google’s Linux implementation
They totally will, if Google will wave the huge user base size in front of them (which Google already did). So MS grip on gaming developers' mind share will fly out of the windows. That's the best thing I see coming out of Stadia and it's something MS clearly are scared of, since when it comes to their gaming business, they are used to lock-in and years of developers' mind share domination, rather than competition on merit.