I don't quite understand this benchmark. Why compare distributions? What's really the difference here? Some different X11 or Wayland settings? Different driver

I don't quite understand this benchmark. Why compare distributions? What's really the difference here? Some different X11 or Wayland settings? Different driver versions? Different kernel or kernel settings? Whatever distribution I currently have, in almost all cases, I should be able to configure those things just as well? So this is just a test about which distro has the best defaults? Ok, it's maybe interesting to some. But the text is misleading, it writes this as "what is the best distro for gaming". For me, much more interesting would be, what are relevant settings to maybe improve the performance, with my distribution of choice.