No, the idiot is correct this time.
Congress DOES have CHECKS AND BALANCES on the Supreme Court.
EACH of the three branches as ways to check the other two branches.
But I rather expect the idiot misstated what Alito’s point was. So lets put it in the ‘stopped clock is correct twice per day’.
The checks and balances comes only IF congress passes a law. Then IF a case comes before the court. That is the only input they have