> For example DLSS does not work on Linux so how can it have better performance that Windows.
What does DLSS have to do with anything?
> Drivers are better on windows
[citation needed]
Anecdotally, I've had way more driver-related stability problems on Windows than I've had on Linux, at least within the last ~3 years.
> games are developped for windows and optimized for it so the vaste majority run better on Windows.
How games are developed is irrelevant; Mesa has different performance characteristics than the respective Windows drivers, and so performs better in a lot of cases due to lower overhead. Projects like DXVK can further improve performance by translating DirectX calls to Vulkan.
In any case, there are plenty of benchmarks online showing some games achieving higher FPS on Linux than on Windows. For a fairly extreme example, see this 3-year-old benchmark[0] showing Dota 2 on Linux wiping the floor with its Windows counterpart in 1080p. I have also personally tested this and noticed an improvement on Linux with certain games. (Granted, not very many, but this was also a few years ago, before some of the recent performance optimizations in Mesa, Wine, and related projects.)
Disclaimer: I'm not a subject expert, so can't go into detail about the how/why, but I also believe the benchmarks speak for themselves.
[0]: https://www.phoronix.com/scan.php?page=article&item=june-201...