The people affected are not all brown people, so even if I held that low a view of the Supreme Court, no I would not bet on that.
Sitting on it until 2030? Well... it won't be the Supreme Court sitting on it until 2030. It will be:
- You can't go to court (usually) on a hypothetical. You usually need someone who has been actually affected. That can't happen until the law actually takes effect (September).
- Then you need a court case, in federal court (probably, since it's a first amendment argument). That has to reach completion, which can take a year or three.
- Then you need an appeal to the district court, and for that appeal to be accepted, and for that court case to run to completion. I have less of a feel for how long that takes, but I would guess at least half a year, maybe longer.
- Then you need an appeal to the Supreme Court, and for it to be accepted, and for the Supreme Court to hear the case and decide. That can take a year.
So, yeah, you're not going to see a final resolution until 2030 or so. That's not because the Supreme Court is sitting on it, though - at least, not most of it.