A previous attempt got macOS Catalina partially running on a Steam Deck. Credit: Lampa183
The modder notes that they, with help from others, “figured out a way to make [macOS versions] newer than Catalina boot” on the Steam Deck handheld gaming device, creating what might be called a “Deckintosh.” The Steam Deck normally runs its own SteamOS 3, a Linux distribution that supports Windows games and apps using a Proton compatibility layer.
This is not the first time a version of macOS has been ported to the handheld gaming device. Using SteamOS VirtualBox, a Reddit user was able to get macOS Catalina booted but not fully running about two years ago.