“That is not what is says, read it again slowly”
Congress has never availed itself of this Constitutional power, but, in fact, it can take certain things off of the table for SCOTUS to rule upon.
If I, a retired social studies teacher, am aware of this, so should a Supreme Court Justice.
Congress removed SCOTUS jurisdiction over Guantanamo prisoners but it went to court and sCOTUS decided they have jurisdiction anyway.