The comment you're responding to was not at all naive: it only says there's no _legal_ way for police to force you to provide this information. You are correct that they can in many ways force you to comply, but none of those ways are legal.

Those ways of applying illegal coercion also break down as more and more people realize their rights and refuse to comply. The more people who force police to act illegally, the more risk there is of trouble for the cop. They can get away with it better if they don't have to do it too often.