So here's how the loophole works. There are 12 courts of appeals. You (ICE) does a bad thing. (renditions a US citizen to an El Salvador concentration camp without due process) You get sued, appeal it to that court of appeals. Let's say it's the 9th Circuit Court of Appeals, let's say you lose. You take the L and move on. You never do the bad thing in the 9th circuit again: that decision is binding. Then you do it again in a different circuit. Let's say you do the bad thing in Texas, where the 9th circuit decision was not binding. Let's say you win this time. Now the 5th circuit is your playground.
From now on, every time you arrest someone in the 9th circuit, you put them on an express flight to anywhere in the 5th district within an hour or so of arresting them, before they can get a lawyer to talk to a judge. The precedent that matters is the 5th circuit precedent, where the detainee is right now, not the 9th district (or anywhere else) where they were detained.
Because the Supreme Court has now ruled that this is a lower court problem, they've effectively blocked anyone from ever getting justice ever again.