Windows as a software package would have never been affordable to individuals or local-level orgs in countries like India and Bangladesh (especially in the 2000’s) that are now powerhouses of IT. Same for many SE Asian, Eastern European, African and LatinoAmerican countries as well.
Had the OS been too difficult to pirate, educators and local institutions in these countries would have certainly shifted to Linux and the like. The fact that Windows could be pirated easily is the main factor that led to its ubiquity and allowed it to become a household name. Its rapid popularity in the '00s and early ‘10s cemented its status as the PC operating system. It is probably the same for Microsoft Office as well (it is still a part of many schools’ standard curricula).
The fact that Windows still remains pirateable to this day is perhaps intentional on Microsoft’s part.
13 or so years ago, whenever the first iPads were coming out, that was my first thought. Why don’t they take their laptops, and have the screen removable that it instantly turns into an iPad? Or a windows computer that does the same thing. Microsoft did it with the surface, and it worked pretty well. Still wasn’t quite what I had imagined, but pretty much was. Apple could have made a killing doing something like that, I’m still convinced (if it was PC based though, not their cell phone/iPad OS).