If you try to visit stadia.google.com in other browsers, you're told to download Chrome instead (see screenshot). This also happens in other Chromium-based browsers, such as Opera and Edge, which use Chrome's engine under the hood.
This has been spotted on Twitter https://twitter.com/tomwarren/status/1212496687949864961, and users report that stadia is fully usable in Edge if the user agent string is spoofed (I can confirm spoofing bypassed the error message, but I haven't done enough testing to confirm it's fully usable).
As you can see from that Twitter thread, this erodes public trust in Google, especially with developers, and feeds into the conspiracy theory that this is done deliberately to 'destroy' other browsers, and is very much against what we (the Chrome team) promote as good practice.
Possible next steps:
If Stadia does not depend on anything Chrome specific, and it works fine as suggested in other Chromium browsers, fix the user agent detection script so these browsers are not blocked.
For browsers that are missing functionality, continue blocking those browsers, but provide a 'technical details' page that provides reasoning, preferably with links to tickets in browser bug trackers for the missing features.
For browsers we're unsure about (features look ok, but maybe we haven't done enough testing), allow the block to be bypassed via a 'continue anyway' button, and make it clear that the experience might not be great.
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