Define "ethical". Depending on the definition, none of the current big companies are ethical, so Microsoft going out of business wouldn't even matter.
And you really need to understand how the world works. Ethical never matters, money matters.
I was thinking about this recently as someone suggested it might be an American thing. But I don't think so - there are plenty of unethical companies in Europe, too. They often manage to exploit some loophole in the law and, say, sell expensive things to old people under some apparently legitimate guises. Or they'll fake car engine tests.
But ethical (=ethically neutral) companies definitely exist, and there are many of them.