I don’t think it’s most yet, but it’s improving fast thanks to the Valve Steam Deck. Bazzite is probably the distro to look at for a machine that’s primarily for gaming; it’s based on the Steam Deck OS, but works on more machines. There are some high-profile games like Fortnite that won’t run on it, but a lot of stuff will, especially if it doesn’t rely on any fancy anti-cheat stuff.