However, one court struck down the Obama administration’s effort to create a similar deferred action program for undocumented parents of US children, ruling that the Obama administration failed to follow the notice and comment requirements of the Administrative Procedure Act (APA). Plaintiffs are sure to argue that the APA also applies to terminating the DACA program, and that the Trump administration failed to do that here. 

this is the best argument i've seen so far. it's a technicality, and just extends the process, but it's at least plausible. lower courts can make curious decisions at times, but the stuff about equal rights doesn't strike me as remotely relevant, in context - it's essentially an argument that it's ok to break the law if you're not white, and that trying to enforce the law on non-white people is therefore just being racist. what these arguments are really doing is warping around the equal rights amendment into an argument for special status for brown people. what equal rights actually means is that the law applies the same to everybody, and everybody needs to be prosecuted the same way - if you're mexican or latvian or whatever else. higher courts won't even entertain these kinds of arguments.

but, it doesn't change the fact that it doesn't make sense to fight for a return of deferred action when the congress appears ready to legislate.