I don't know that Microsoft has ever made that claim. The original Xbox was the closest to standard PC hardware, and even it diverged somewhat from what was av

I don't know that Microsoft has ever made that claim. The original Xbox was the closest to standard PC hardware, and even it diverged somewhat from what was available on standard PCs at the time at both a hardware level and API level. The common APIs make it easier to develop cross-platform, but the platforms are still different.