A federal judge has ordered the U.S. Environmental Protection Agency to further regulate fluoride in drinking water because high levels could pose a risk to the intellectual development of children.
Not really. You are just viewing from the wrong perspective. From study perspective, you are right, but the article is talking about legal aspect. Ever since the Supreme Court overturned Chevrons doctrine, courts now decide not experts what and how regulators can create and enforce rules. So EPA was ordered to do so after the study came by the judge.