Does Windows 7 support Blu-ray HD discs?

As a new generation of data storage carrier, Blu-ray is much larger than the current DVD. At present, it can maintain 400G data on a single disc, and has become a distribution carrier for many high-definition movies. However, due to cost issues, it has not been popularized. Windows7 as Microsoft's latest operating system, how about support for Blu-ray?
Unfortunately, although a Microsoft executive has disclosed that Windows7 does not support the video stored on Blu-ray Disc, although Windows Media Player can support DVD. Play, but Blu-ray DVD playback may require a fee to purchase related upgrades or plugins to support. Fortunately, Windows 7 supports Blu-ray Disc burning, and we can use Windows to burn data to Blu-ray DVD. I believe that since WMP starts to support HD video playback, why not consider directly supporting Blu-ray video playback? It may have something to do with the cost of Blu-ray.