This is a list of games (by default sorted by popularity) and their compatibility with Linux. Some games work great, but there are major games like PUBG and Destiny 2 that don't work at all. Some major games like Apex Legends require tweaking to work.
If you're a hardcore gamer, then you need Windows because the games need Windows.
Though this may slowly change over time since Valve put out the Steam Deck which runs Linux.
NVidia and AMD usually design their GPUs together with Microsoft, OpenGL and Vulkan then play catchup with extension spaghetti until some subset of it gets available as standard feature.
DirectX isn't much better with regard to the extension spaghetti. At the very least when you see a OpenGL or Vulkan version you can be assured that w/e that version includes is supported. With DX you can have something claim DX12 support but in reality it only actually supports some variation of DX10 or 11 through the feature level nonsense.
Is this totally true? Vulkan supposedly derives from AMD’s Mantle API. Yes Vulkan and OpenGL have extensions in between major releases, but is that worse?
Yes, coding against extensions means multiple code paths, hardly any different than using multiple APIs when the semantics from multiple vendors don't match 1:1.
In addition to graphics libraries, a lot of anti-cheat is still windows only. Many gamers hate anti-cheat, but by popularity many top games require it.
Microsoft is likely to tie future games in to being Games Pass exclusives, as well as using Microsoft Pluton and TPM chips to use remote attestation in DRM and anti-cheat - so you can't replace your OS or bootloader and still play, etc. (like anti-jailbreak checks on phones).
