2nd: In all Cases affecting Ambassadors, other public Ministers and Counsuls, 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. Congress has the control to define purview and even set terms of federal judges including the supreme Court. The fact they originally defined terms as "until death" notwithstanding, they can change that at any time they want as well.
Congress has the control to define purview and even set terms of federal judges including the supreme Court. Define purview for lower courts, yes. But terms are defined by the Constitution, as is the jurisdiction of the Supreme Court. Congress cannot overrule that.