AMD GPUs are good enough, cheaper, and actually available for purchase. I also appreciate that they have good open source drivers and don't need any fiddling to get working on linux and BSDs.
Intel is also somewhat making ground with their Arc GPUs.
The key to doing well in the gaming market are good prices, and good gaming performance with DirectX and Vulkan.
Intel has been chipping at Nvidia and AMD has been pretty flat.
https://wccftech.com/gpu-shipments-continued-to-decline-in-q...