We tend to forget Apple would probably be gone if Microsoft hadn't bailed them out in 97 (not out of altruism but because of antitrust).What “saved” Apple was the iMac in 1998, not Microsoft.
Microsoft bought $150 million in non-voting stock in Apple as a show of good faith. Apple made Internet Explorer the default browser for the Mac and Microsoft committed to Office for the Mac. At the time, Internet Explorer 5 for the Mac was the best browser on any platform.
After the 5 year period, Microsoft sold those shares, making a huge profit.
At the end of the 5-year agreement, Apple shipped Safari 1.0, based on the KHTML codebase and the rest, as they say, is history.
Ironically, Microsoft's browser is now based on a fork of the engine of the browser that replaced IE on the Mac back in the day.