Until now, previous versions of Windows that 8 and 8.1 by some gamers are considered less suitable for playing games. The main problem is still around the compatibility and games that support full features of the operating system. Microsoft announced that Windows 10 to play the game would be better.
The relationship of Windows 10 and the experience of playing a better game is because along with the release later, you will get DirectX 12 which embedded in Windows 10. For Technical Preview version it will not exist. Apparently, Microsoft will make DirectX 12 exclusive for Windows 10, like previous versions.