Recent testing revealed that Arch Linux, Pop!_OS, and even Nobara Linux, which is maintained by a single developer, all outstripped Windows for the performance crown on Windows-native games. The testing was run at the high-end of quality settings, and Valve's Proton was used to run Windows games on Linux.
1 % lows are likely a driver thing (Nvidia calls it “Game Ready Drivers”), with Arch you’ll get new drivers (or kernel versions) much earlier, similar to Windows.
… Then why did they get the results that they did in the article?