The original law (like many laws that delegated congressional authorities at the time) contained a legislative veto provision which gave the legislative final oversight of any administrative action. In the 80’s the Supreme Court found that legislative veto provisions were unconstitutional, but left all of those delegations standing. After that ruling, the administration can now do what it wanted without congressional oversight and the ability to veto any attempt to repeal the laws. In the oral arguments, Gorsuch raised the possibility that the law itself should have been found unconstitutional in the 80’s because the legislative veto was essential to its function. It looks like the court today took a minimalist approach, letting these delegations stand but minimizing the scope of the powers delegated.