Healthcare is "free" across Europe, including in The Netherlands. The choice of The Netherlands' to structure their system as mandatory insurance doesn't change the nature of it, it is free at the point of service with the mandatory insurance costs paid for by the government when someone is unable to pay themselves.
No matter your mental gymnastics that is not how those Americans imagine health care in Europe works. And just for your (and our confused American friends) information there are several countries in Europe where "a point of (healthcare) service" will send you a bill.
Which European countries have a healthcare system similar to the American system? A system that has "insurance" (e.g: The Netherlands, Germany) is no less "free" healthcare than a system without insurance (e.g: England) or a system that will "send you a bill" like France. "Free" healthcare means that the patient will never need to worry about the cost of their treatment because it is covered by the system (whether through taxation, reimbursement, insurance does not matter). How many people have been bankrupted by healthcare in Europe?