The title here is misleading. A game not being supported can be completely ok. The vast majority of games ran through Proton on Linux aren’t and they typically work perfectly fine regardless.
As the announcement itself says, they have actively chosen to not enable the setting that would allow Linux, but is working to support it in the future, presumably to get it SteamDeck-verified for the real launch.
The title here is misleading. A game not being supported can be completely ok. The vast majority of games ran through Proton on Linux aren’t and they typically work perfectly fine regardless.
As the announcement itself says, they have actively chosen to not enable the setting that would allow Linux, but is working to support it in the future, presumably to get it SteamDeck-verified for the real launch.
In the beta last week the game was perfectly playable via proton which is why people are frustrated.