According to a Valve Engineer, the Steam Machine specs outclass the most common PC configurations. The company relied on its own hardware surveys to choose the system’s components. Even as an entry-level option, Valve claims that 4K/60 fps performance is realistic, despite a memory-limited GPU.
and starting with this model leaves room for a “steam machine pro” for people that want more, just like playstation has done
… and also perhaps a “steam machine lite” for people that just want a little bit of retro/2d gaming on their tv