Indeed, the reaction to this from lawmakers is really perplexing. They're claiming that the Court is "rogue" or something, but if you actually read what they wrote they are returning power from the executive to congress (or making it clear that Congress always had this power, not the executive). The reaction makes me think there are many lawmakers who are rather uninterested in making laws, and instead actually do want to see unelected Judges and executive bureaucrats implement their preferred policy options instead of doing the (hard) work of writing and passing those policies themselves.