“Why should a company that builds computers make computers that can run any operating system? “
Simple... Because when you purchase it they do not own it anymore you do. Would you buy a car from a manufacturer who forces you to only buy your gas from one source? Or force you to only allow certain people or products to be carried in it? A car that forever belongs to the manufacturer of that car and never you?
No... And it should not be like this with computers either. It is NOT theirs anymore once you purchase it. And this is what MS and manufacturers are doing... They are bullying consumers in to allow them to retain perpetual ownership when they have no right. It does NOT belong to them anymore and the consumer should have the right to do what they like with the product they purchased.
The marketplace would ensure a car that onl ran gas from one company would not sell. There are plenty of companies building systems that will run Linux or the operating system you chose. If that was a consumer demand then those companies would grow. No need for the Gvt to choose winners or control the product line.