IBM's OS/2 was able to run DOS and Windows problems. OS/2 was billed as "a better DOS than DOS and a better Windows than Windows".
I've always thought that feature was actually OS/2's downfall. Back in the day when I had to make a choice whether to develop for Windows or for OS/2 I chose Windows because I knew that my program would run on both Windows *and* OS/2.
So, implementing Android compatibility guarantees that nobody will develop for Windows Phone. As OS/2 proved, making Windows Phone a "better Android than an Android" is a losing strategy.