The regulators have taken a whack-a-mole approach to banning this class of chemicals in the past. The result is that the popular ones that are well-understood

The regulators have taken a whack-a-mole approach to banning this class of chemicals in the past. The result is that the popular ones that are well-understood get banned, and then replaced with ones that haven't been studied. There's no reason to think the replacements are better or worse, though they are often worse. The organization in the article is proposing banning production of the entire family of chemicals (~ 12,000 of them) instead of doing it one at a time.