Nvidia is better for gaming on both Linux and MacOS. Basically, it’s better for gaming on every OS except Windows. Windows has DirectX, which really levels the playing field. Sure, there’s Vulkan, but that’s going to take a while for it to even come close to catching up with DirectX in terms of implementation.

Most game development companies are perfectly happy with DirectX and (if you’re lucky), OpenGL.

And even the companies that make games in OpenGL don’t always release their games on Linux. For example, it would be really nice if Blizzard released their games for Linux.

Though, PlayOnLinux makes it pretty easy to get Windows games running on Linux.