I, for one, would actually be fine with buying a Steam Deck at that price just so that way Steam/Valve have incentive to continue their work on Proton (their answer to try and get unsupported games working on Linux and their own official SteamOS).
The trade-off of giving them incentive to work on Proton, which would help an estimated roughly 2.5 million "monthly active users" using Steam on Linux definitely seems reasonable to me at least.