Nah, Microsoft should go back to being a UNIX developer and vendor. Long before MS-DOS, and throughout the 1980's, there was XENIX... y'all remember XENIX, right?
From Wikipedia:
In the mid-to-late 1980s, Xenix was the most common Unix variant, measured according to the number of machines on which it was installed. Microsoft chairman Bill Gates said in 1996 that for a long time that company had the highest-volume AT&T Unix license.
They had Xenix before MS-DOS, but not before their BASIC interpreter business..