There are thousands of games that come out every year, even after filtering out the asset flips and hentai games. A handful of those will have kernel-level anti cheat that make them incompatible by design. Fewer still will be pushing minimum specs that are too hefty for the Steam Deck to handle. So the thousands of remaining games are your use case for the Steam Deck, which tends to be cheaper than its competition and comes with a better OS. A device like those Android ones are fine for emulation, but you're not playing newer releases on it, and newer releases are far, far, far more than just AAA games with hefty system requirements; it's also Mouse: P.I. for Hire, Fatal Fury: City of the Wolves, Warside, Descenders Next, Dispatch, and on and on.