The popularity of Windows is largely due to the fact it’s pre installed on most PC’s when you buy them, people literally think Windows ‘is the computer’. Such popularity has little to do with Windows being a great OS. In many ways Windows is like McDonalds: It’s not the best, it’s not the worst, it just fills that hump in the bell curve.
Due to the fact Linux has no marketing department, it’s unlikely this will ever change.