Valve tried selling Linux boxes for gaming back in 2013, but noone wanted to sell/make/buy them b/c the library wasn't there and it's a hard sell when Windows is already baked into OEM hardware pricing anyways (so it wasn't any cheaper to buy a pre-made Steam Machine than it was a similar-spec windows box).
What was the last time?
Valve tried selling Linux boxes for gaming back in 2013, but noone wanted to sell/make/buy them b/c the library wasn't there and it's a hard sell when Windows is already baked into OEM hardware pricing anyways (so it wasn't any cheaper to buy a pre-made Steam Machine than it was a similar-spec windows box).