While I agree it's unreasonable, it's also kind of a chicken and an egg thing. These things won't change until Linux becomes big enough to ignore. I'm not sure what the solution is though, as I don't think it's realistic to make people give up what they enjoy to get there. That's not gonna happen. But Valve has at least made a dent with the Steamdeck and Proton in general, and maybe more with the upcoming Steam Machine. Devs actively target the Steamdeck nowadays for games where it makes sense, so it is taken into consideration at a whole new level compared to years past.