"Apple played this closed market approach with the desktop and look where it got them:" It got them in the position of being the ONLY company making consumer computers that still has any margins to speak of. HP, Compaq, Dell, et al are all racing each other to the bottom, trying to eke out a minimal survival on razor-thin margins.
Apple's stumbles in the 80s and 90s weren't because they failed to license MacOS, it was because Jobs was immature and shot himself in the foot, taking his company down with him. These days they couldn't possibly be doing any better, and you can bet your ass Jobs still thinks licensing MacOSX is a terrible idea.