The matter is very significant, as a few hours with the briefing will show, and the impact intergalactic.
That's...not in dispute. They aren't bringing the case, so they don't need standing.
> Why the Court has requested input from the White House is difficult to understand.
They didn't ask the White House, they asked the Solicitor General (a Justice Department official whose office represents the federal government at the Supreme Court.) Which is fairly routine in important questions involving construction of federal statutes, because even if they aren't parties to the immediate case, the federal government obviously has an important interest in the meaning of federal law.
> The matter is very significant, as a few hours with the briefing will show, and the impact intergalactic.
Which is why it would probably be more surprising if the Court did not invite the Solicitor General to file a brief laying out the government position.