Threatening is a given. Complaints about betrayal also a given.
Since SCOTUS was established directly by the U.S. Constitution (Article III, Section 1) it would be interesting to see if and how he tries that. I think it more likely he calls for impeachment/removal of certain justices, especially those he appointed. Kavanaugh wrote the dissent (along with Alito and Thomas) so he's 'safe'. But I expect to hear a tirade against Coney Barrett & Gorsuch, if not by name certainly by inference. And I expect to hear the word 'disloyal' in some iteration at some point.
I expect mucho roadblocks by the Administration in effectuating this decision. And although SCOTUS is the final 'decider' that won't stop the Administration from finding some other challenges to the lower court decision this was based on. This used to be very common in death penalty cases in order to prolong the stay of execution. If the attorneys found multiple reasons/faults with the case they'd file appeals one after the other as each appeal was denied. Now all reasons for appeal must be filed at one time. Not sure if this applies to all cases, or just criminal ones.
What is sure is that the consumer will not see one penny of any tariff refunds, nor will prices go down.