It’s congressional prerogative where to set the courts limits.

The courts would be able to weigh in on whether that jurisdiction striping was itself allowable.

And, of course, we would have to win the House back and hold the Senate/White House in able to get anywhere (and overcome a filibuster).

In short - an exercise in wishful thinking in the near term

Congress can completely get rid of all circuit courts and only leave the Supreme Court with the jurisdiction expressly written into the Constitution if they so chose.

That would require 67 Senate votes so that part isn't ever happening but otherwise there's no jurisdiction to be weighed by the Court. It's explicitly the power of Congress up to the limits of what is given to the Supreme Court by the Constitution.