Does that mean you can ignore the laws of Thailand while you are here as a non-immigrant? Do what you like and just point to the stamp in your passport when arrested?
Your visa/permission to stay/immigration status has no bearing whatsoever on your duty to follow all the laws of whatever country you are in. And in this case, the law is quite clear - spend 180 days or more in the country in any calendar year and you are a tax resident for that year, with all the obligations that go with it.