Google stadia was launched a few months ago to much fanfare. But the launch hasn’t exactly been smooth and customer interest is lacklustre at best. The service would have been far better had it used Windows instead of Linux.
How cloud gaming works
Player Input → Network → Input Service -> Game -> GPU Driver -> Operating System -> Video Encoder -> Network -> User
Google optimized many parts of the above stack. To get the latency from the input to network down, they created their own controller which connects to Wifi. It runs games at 120Hz or 60Hz to ensure that the time taken to render a frame is less than 16ms. Other competing cloud gaming solutions like Parsec, Vortex etc use Nvidia GPUs for video encoding which take 15+ms to encode h264 video and this figure is higher if you do H265 (which is required for 4k video streaming), while Google built their special hardware encoder which is able to encode streams much faster. And it is using Google’s Edge servers to make sure that latency is as less as possible for the end-user. Now all of these aspects are custom built and don’t have anything to do with the operating system and hence would have been applicable even if google launched on Windows. The only aspect which would differ is the GPU driver and the Operating System. But software like Looking glass can capture frames in Windows in < 10ms and there are many other cloud gaming providers like Geforce Now, Parsec etc which use Windows without any issues. DXGI on Windows is used to capture frames and it is an excellent and versatile framework. And since the role of the operating system is so minimal in the whole flow, that I wonder why Google even chose Linux. While some may point out that Google uses Vulkan instead of DirectX, Vulkan is available on Windows too. So any tooling that Google custom-built for Vulkan should be usable on Windows too.
Netflix of Gaming
When Stadia first came out people were comparing it to Netflix and it was called the Netflix of gaming. While it is far from an all-you-can-eat service which people thought it was, it is wrong to compare it to Netflix for another reason.
When Netflix first started its online streaming service they had one big advantage. They could add any existing movie or tv show to their online library on securing a license. DVD ripping is a straightforward process and only takes a few minutes and all Netflix required to add a DVD was a licensing deal with the content owner. Stadia doesn't have this luxury since it runs Linux and Game studios barely develop for Linux. So not only does google require a license from the game studio, but it also need the game developer to port it to Linux and to Stadia's platform. For getting Destiny ready google had to deploy 2 of their engineers in Bungie's offices for 6 months to make sure that the game could release on time. And even after doing that, the game still runs at 1080p and is upscaled to 4k. Recently there have been reports of Game developers running into problems with the Linux scheduler and with Linux Torvalds proclaiming that the scheduler isn't the issue, these issues won't be going away soon.
Had Stadia used Windows, it would have actually been the Netflix of Gaming. Every single game released on Windows would have been playable after securing a licensing deal. Game developers wouldn't have to make any efforts to port a game to a completely new platform. Rather than waiting months for game developers to figure out issues with Linux and port it to Stadia, it would have been able to add games to its service quickly.
Multiplayer is a huge aspect of gaming these days. I have been a gamer for over 20 years now and 99% of the time I play multiplayer games. For me to play a multiplayer game on Stadia, my friends also need to play that game on Stadia. If your friends have gaming PCs then you are purely out of luck since you cannot play with them. Destiny 2 is a social game with many areas full of people, which are notably empty on Stadia. Multiplayer modes like Crucible sometimes end up having match times of more than 15 minutes.
Had stadia used Windows, they would have been able to tap into the already existing player base. Not only would people be able to play with their friends who already have gaming PCs, but multiplayer modes would have been much easier to join. Lobbies would have a lot easier to fill up and MMORPGs like Elder Scrolls Online would actually make sense.
Since Stadia purchased on Stadia remain in the cloud, you won't be able to play the game in case Stadia shuts down. And given the huge number of products which have been killed by Google in the past, this is also not very unlikely. And games need to be purchased on Stadia just like any other platform. So if you own a game on PC or other consoles, you still need to purchase it again. A lot of other cloud gaming services like Parsec, Vortex allow you to bring your own PC license. So even if those services shut down, you would still own the game and be able to play it on your own gaming PC. As someone who owns over 120+ games on Xbox , it gives me anxiety to think about what would happen if suddenly one day my whole game collection was unplayable.
Had stadia used windows, people would have been able to easily download their purchased games in the event of Stadia shutting down.
To summarize, Google Stadia would have been a much better service had they used Windows. It would have had more games, full lobbies, ability to play with friends who are on PC and be devoid of problems with game ownership. Game Studios would have been able to launch their game on Stadia with zero or negligible effort. For a company like Google, the cost of Windows licenses would be minuscule compared to the cost of sending over its engineers to debug issues faced by game developers. And while they have done an impressive job at solving the other tech problems like no other cloud gaming provider, they erred by choosing the wrong platform where it matters most. The problem that Google is trying to solve today is to make Linux a gaming platform. A problem that very few people care about.