Playstation, Mac OS and many others are based on BSD for that reason (and probably other reasons as well).
I cannot imagine a BSD-based MS Windows but it would be cool!
This would probably solve slow filesystem I/O (which is one of the major pain points for me when working under Windows, especially if you have a large number of small files).
However, it's important for Windows to keep backward compatibility for applications using old APIs. I think that's a major selling point vs. other platforms.
On the other hand, in my experience WINE runs older Windows apps better than my modern Windows 10 install does. Most things ~pre-2005 run really well, especially games which just refuse to boot on modern Windows (or require compatibility patches).
I cannot imagine a BSD-based MS Windows but it would be cool!
This would probably solve slow filesystem I/O (which is one of the major pain points for me when working under Windows, especially if you have a large number of small files).
However, it's important for Windows to keep backward compatibility for applications using old APIs. I think that's a major selling point vs. other platforms.