Yeah if by breakthrough you mean shits the bed. The reason OSX works so well is because Apple has a limited set of hardware they have to support vs the wild west of hardware that windows has to support.
Switching models to compete with the Windows model is a mistake they were lucky to make once and live to tell about. They will not make that mistake again.
If you're looking for competition against Microsoft, look to Google. Both of these companies aren't hardware companies at their heart, and both want manufacturers to bundle their OS.
I'd say that if Microsoft had an ally, it would be Apple today (only in the sense that Apple doesn't care for Microsoft's business).