TL;DR: Valve launched the Steam Frame VR headset with an Arm-based Snapdragon chip, aiming to run Half-Life: Alyx natively and streamed from PC. The new hardware features a “Frame Verified” status for optimized games, while rumors suggest two upcoming Half-Life titles supporting PC and VR cooperative play.
You can already run Steam games on Android, using the same protocol as Valve (FEx) with an app called GameNative.
Not Android, phones based on a desktop Linuc distro (e.g. PostmarketOS, Ubuntu Touch)