Ok - according to your link the test is free. But it costs $3200 to visit a doctor to get the free test. Am I reading that correctly?
The test (as of now) is free. I am pretty sure $3200 is not representative of what a US citizen typically pays for a doctor visit.
One anecdotal instance of how much someone spent on emergency care really should not be misrepresented as 'the cost of a Coronavirus test [in the US]', especially since it may discourage those who think they may need to be tested from doing so.
The first thing you have to know about the US is that a large portion of the population has no health insurance, does not go to the doctor, and has probably only seen a doctor a few times in their lifetime.
They don't have a doctor, don't really know where to find one on short notice, and aren't going to wait for an appointment if there is something so extreme as to get them to see a doctor. They only use emergency rooms for care, and some never intend to pay. Hospitals know this, which is why they charge $3000 for a visit to the emergency room (this is a real number btw from personal experience taking an ex girlfriend). Their collection department is hoping to get a 10% return on the amount they bill through collection agencies.