I think it's a very Valley-centric opinion to think Microsoft doesn't have any consumer customers. Even putting aside all their other end user products consumers buy (XBox, the utterly dominant Office).

I certainly don't agree with your definition of a customer. People who buy a PC with a Windows OS on it know it's a Windows OS, and make that choice willingly. It's like pretending nobody is an Android customer because they buy their phones from Samsung not Google.