Yup, it uses flathub as its back end. You can also install distrobox on SteamOS, which can be used to install containerized packages from other major distros, though I haven't really messed with that.
Between Microsoft turning Windows into a massive surveillance system and Apple telling people what they can and can't do with their Macs(really, you have to go through some hoops on their newer versions just to run unsigned apps....) a company like Valve pushing an actual open platform(at least as far as the OS goes) is kind of a breath of fresh air. I know multiple companies DO sell machines with Linux pre-loaded and some even specialize in such things, but they simply don't have the brand recognition that Valve's Steam platform brings.
Between Microsoft turning Windows into a massive surveillance system and Apple telling people what they can and can't do with their Macs(really, you have to go through some hoops on their newer versions just to run unsigned apps....) a company like Valve pushing an actual open platform(at least as far as the OS goes) is kind of a breath of fresh air. I know multiple companies DO sell machines with Linux pre-loaded and some even specialize in such things, but they simply don't have the brand recognition that Valve's Steam platform brings.