Fortunately, it looks like Valve is working on that. The Verge spotted a line in the latest release notes for SteamOS, stating that it was adding support for hardware keys on the ROG Ally.

Valve is reportedly working on a follow-up to its Steam Controller, along with a new VR controller for a new headset.The Latest Tech News, Delivered to Your Inbox. Digital Trends.

If Valve was the only company working on VR and it did for PCVR what it has done so far, VR would’ve died a long time ago with nothing much VR to work on or be in a position to push it forward.

A few days ago Valve reworked the main navigation bar in its Steam Store and removed a direct link to buy Steam Machines, the Linux-based boxes it hailed as an open alternative to macOS or Windows ...

Valve working to fix Greenlight bottlenecks. Steam curation process marks first anniversary by approving 100 new titles; Gabe Newell says there's still a ways to go.

So, yes, we are very much working on new tools and new ways of getting data out of Steam, and we hope that data can be more accurate and more useful than what Steam Spy previously offered you." ...