[ascagnel_]

It’s the obligation of the developer to make sure their game runs acceptably on supported platforms and on systems that meet the stated requirements.

If Valve is offering supplemental support on top of what the developer is offering (eg: running Windows games on the Steam Deck via Proton), then its Valve’s obligation to keep things running, as the developer has never committed to keeping things running outside their supported platforms. That said, additional support from the developer (eg: Microsoft/343i for Halo, Respawn for Apex Legends) to get games running on other platforms is always appreciated.

[slowhadoken]

It would be ideal but it sounds like too much runaround for Valve.