Looks like this is just fifth circuit.

That being said, there's a lot of stupid arguments being made. Like instead of focusing on nonsense like us doing better in college than the local cletuses the focus should be on discretion - the government has broad authority whether to initiate removal proceedings, actually remove you pursuant to a removal order, and to dismiss proceedings if removing you is no longer in public interest or to agree to admin closure if you are seeking some other means of legalizing your status.

Another part should be the precedents for having this power. Deferred Action has essentially existed in some form since at least the 1970s (and likely even longer) and has been time and time again used to patch holes in immigration laws. For example, the largest application to date is not DACA, in fact it was what eventually became Family Unity to keep families with mixed eligibility for the 1986 amnesty together. Similarly another large groups these days are those with prima facie determinations on VAWA self-petitions and U-visa applications with prima facie determinations. Technically the same could apply to T-visas but T-visas don't ever hit the statutory cap.

It also remains as something granted on case by case basis in removal proceedings by ICE.

Next up even if it was never properly codified in law there are laws that directly acknowledge it like the Real ID Act which is an implicit acknowledgement that the executive has the power to grant deferred action as otherwise such an acknowledgement would be just a dead letter.

Then it's the fact that the government has other powers like the extremely broad parole power (recent beneficiaries were Ukrainians and Venezuelans, largest group by far were Cubans during Wet Foot Dry Foot) to allow in persons otherwise ineligible or legalize those already in the country. If if push came to shove could very well convert all DACAers into parolees.

Last is lack of standing from the states bringing the lawsuit. One is that Real ID Act mandates them to issue driver's licenses. Second is that even if they have to "subsidize" issuance of such licenses they would have to prove damages as a part of a greater whole. Where one they are better off not having unlicensed motorists on the road, and second is that people who work legally and earn more also pay (more) taxes (be it income taxes or sales taxes). Finally is that states could offload those extra costs by increasing fees either wholesale or on DACAers specifically or win some order exempting them from having to issue them to DACAers. I.e. there exist ways to address to address the alleged damages without tossing the baby with the bathwater.