In all Cases affecting Ambassadors, other public Ministers and Consuls, and those in which a State shall be Party, the supreme Court shall have original Jurisdiction. In all the other Cases before mentioned, the supreme Court shall have appellate Jurisdiction, both as to Law and Fact, with such Exceptions, and under such Regulations as the Congress shall make.
Seems pretty clear.
Even if they want to say they can only regulate jurisdiction, then fine, take away their jurisdiction. We’ll just have circuit splits.