This is from snippets of Justice Sotomayer's disent I found here.
Sotomayor said that the majority opinion, written by Chief Justice John Roberts, invents "an atextual, ahistorical, and unjustifiable immunity that puts the President above the law." Their ruling, she went on, makes three moves that she said "completely insulate Presidents from criminal liability." Sotomayor said the court creates absolute immunity for the president's exercise of "core constitutional powers," creates "expansive immunity for all 'official acts,'" and "declares that evidence concerning acts for which the President is immune can play no role in any criminal prosecution against him."
You aren't missing anything. Our Supreme Court is supposed to look at each case and make sure that the law was applied correctly according to the constitution and case law, but has now become an extension of Trump's legal counsel doing backflips to bend (and inow seems also rewrite) the law to his benefit.