They haven't really been betting on Linux at all for about two years. All major development efforts, at least consumer facing ones, have pretty much stopped. SteamOS now is as bad as it was when the Steam Machines released, which are still awful. Feral and Aspyr are pretty much the only two games in town nowadays producing consistent and good Linux ports of AAA titles. And they are just that, though - ports. Neither company has the developer manpower or budget for their ports to make good native OpenGL games. Likewise, the other major source of Linux titles is Unity, whom also haven't invested much in making a well optimized OpenGL rendering engine compared to their DX one.
The end result is that games run poorly on Linux and give a terrible experience to anyone trying it, because nobody wants to invest in native titles that are as optimized as the Windows ones... besides Valve. Pretty much every Valve game runs as good or better on Linux than on Windows, but they were the exception able to throw what is in all likelihood more money than they have made from Linux users in their first year on the platform to port these titles correctly.
Top it off with how bad the uptake on Vulkan has been relative to DX12, and the future is not bright for Linux gaming. It is way better than it ever was, and for anyone except a hardcore gamer the library is definitely vast enough to not feel any desire to use Windows over Linux for the sole reason of gaming, but its in such a shoddy state it won't win over hearts or minds any time soon.
The end result is that games run poorly on Linux and give a terrible experience to anyone trying it, because nobody wants to invest in native titles that are as optimized as the Windows ones... besides Valve. Pretty much every Valve game runs as good or better on Linux than on Windows, but they were the exception able to throw what is in all likelihood more money than they have made from Linux users in their first year on the platform to port these titles correctly.
Top it off with how bad the uptake on Vulkan has been relative to DX12, and the future is not bright for Linux gaming. It is way better than it ever was, and for anyone except a hardcore gamer the library is definitely vast enough to not feel any desire to use Windows over Linux for the sole reason of gaming, but its in such a shoddy state it won't win over hearts or minds any time soon.