Showing my age, but I was working on an application for the Apple Macintosh when that meant doing the development on an Apple Lisa. I was so impressed with the new interface: windows, icons, menus, pointers. When I first encountered Windows about a year later, it seemed such an amateurish copy. I was amazed, years later, that Microsoft were not accused of plagiarism.
Having said all that, Microsoft had the wisdom to make Windows available to the wide world of developers. Programs were developed for Windows that could not be developed on the Mac (because of Apple's rather closed approach). From what I hear, it's still the case that Windows offers a wider array of possibilities.