

Tuxedo OS as far as i know is an optional distro they give preinstalled. You can buy them with no OS and install one yourself via usb it takes like 15 mins. This is true of any laptop with an unlocked bootloader (something like a mac can be done but its harder.)
Is it using Wayland or x11? Try switching to X11 if on wayland. Theres a scaling issue on wayland in certain versions where it thinks your screen is a MUCH higher resolution than it actually is. Its meant to help with high dpi displays by using digital pixels but on lower dpi displays it can mess up stuff especially in certain software like games.