I'm so glad they did this and chose a legit license (MIT license). This is so important for historical reasons. It's a bit jarring for me to see this particular logo, since I have a lot of personal reasons to think of this logo as "the MS-DOS 5.0" logo (and I think the logo was indeed launched with 5.0 in 1991 rather than with 4.0 in 1986). In skimming the Wikipedia article, it may be that IBM's PC-DOS 4.0 is what most Americans remember running (for those of us that remember computing in those ancient years):
en.wikipedia.org/wiki/MS-DOS_4