Also, from a legal liability standpoint, it's a near guarantee that SOME trivial quantity of open source code snuck in at some point in the last few decades. No

Also, from a legal liability standpoint, it's a near guarantee that SOME trivial quantity of open source code snuck in at some point in the last few decades. No matter how great your intentions are, somebody will have done it wrong, and the legal openings from "you used our copyrighted stuff to make Windows now pay us" is probably substantial.