Slimebeast on 23 June 2016
First, because there is no exsisting Skyrim version at all on XBoxOne or PS4.
And second, by giving it for free to those who already own Skyrim with DLC on PC, it's a sign of respect from Bethesda to the whole PC community for supporting not just Skyrim but the whole Elder Scrolls series for decades, and especially thank the guys who make and enjoy mods.
