To expand on point 2, Europe is already home to two major competitors to Windows (one headquartered within the EU) as well as competitors in other fields, so they would also have an easier time (as a bloc) than many other places, who don’t have local competitors I nearly as good a position.
Yes, technically they could cause massive disruptions. Not likely they will.
They would not get paid.
Europe would suddenly have a very good reason to spend billions of euro on funding competitors.
To expand on point 2, Europe is already home to two major competitors to Windows (one headquartered within the EU) as well as competitors in other fields, so they would also have an easier time (as a bloc) than many other places, who don’t have local competitors I nearly as good a position.