Steam isn't the Steam machine. If somebody's on a budget a PC you could get for a couple hundred is way more than enough to run nearly all games on Steam; $600 could get you a beast of a machine. I don't really know who the market for the Steam Machine is, because that price is kind of insane. I suppose we'll see how things look in a year or two there.
> $600 could get you a beast of a machine
Where can you get a new gaming "beast of a machine" for $600? In the past you could build a reasonable gaming machine for $600 but parts are drastically more expensive today.
If you go to microcenter and look for gaming PCs, their cheapest option is $800 [1]. PC Part Picker's entry level build is $780 [2].
The only option I found with these constraints is this computer from Walmart with a GPU released in 2017 and a CPU released in 2013 [3] (This is not a recommendation for this listing. Please don't buy it).
[1] https://www.microcenter.com/product/705867/powerspec-g530-ga...
[2] https://pcpartpicker.com/guide/fQscCJ/entry-level-amd-gaming...
[3] https://www.walmart.com/ip/STGAubron-Gaming-PC-Computer-Desk...