It's true that Microsoft gave Apple an infusion of cash and guaranteed software support for the Mac platform just when it needed it most, but Microsoft was not doing it to be benevolent. It was just beginning to defend itself from the accusations of being a monopoly and needed a "harmless" alternative to the Windows ecosystem they could point to. At the time, Microsoft needed Apple to survive.
Microsoft never thought in a million years thought Apple could ever be a serious competitor to their core business. After all, Microsoft's main business was selling software to computer manufacturers, while Apple sold consumer computer systems directly to a limited subset of consumers. To Microsoft, Apple's competitors seemed to be the likes of IBM, Dell, Gateway, Compaq, HP, Packard Bell, etc., all of which purchased their software from Microsoft. With an over 90% market share, Microsoft didn't seem to have anything to worry about from the "beleaguered" Apple.
Fast forward about a decade and a half. The internet has exploded and become the primary way people get and store information. For the first time in computer history, you are less tied to a specific application written by a specific company to access information. As a result, Apple's computer market share is over 10% for the first time since 1994. More and more people are even using non-PC devices to access information. In the exploding smart phone market, Microsoft is now in third place behind Research In Motion and Apple. And with Google now throwing its hat into the smart phone market ring there is even more competition in that sector.
Microsoft is competing with Apple the mobile music device market, and losing. Microsoft is competing with Nintendo and Sony in the home video game market, and losing. Microsoft is competing with RIM and Apple in the smart phone operating system market and losing. Microsoft is losing on a lot of fronts.
Sure, Microsoft is winning is in PC operating systems and PC business software. But as more and more people realize that they don't need a PC with Microsoft software to access and process their information, that market will become less and less important and will lose "share" to seemingly unrelated market areas.
Make no mistake, Apple and Microsoft and Google and Sony and a litany of other technology companies are direct competitors in the, as yet, undefined "electronic information access" market.
As much as the iPhone is locked down, Apple still seems to remember that it is damned near impossible to make a successful computer systems or information access devices without successful third party support. And it gets real complicated when your third parties are also your competitors. Which competitor should Apple help gain a foothold in a market they are nearly dominating? Microsoft? Google? Of course, the simple answer is neither, but that just would hurt Apple in the long run.
Now that we are emerging from the dark ages of the Microsoft monopoly of computer tech, we are headed into very interesting times indeed.