The usual reasons, evil big corp monopoly with a user-hostile business model etc.

I still use their products. But if I had to pick a company to win the next gold rush, it wouldn't be an incumbent. It's not great that MSFT is winning either, but they are less user-hostile in the sense that they aren't dependent on advertising (another word for "psychological warfare" and "dragnet corporate surveillance"), and I also appreciate their pro-developer innovations.