SCOTUS did not say there is no validity regarding Donald Trump's insurrection activity and the 14th Amendment clause forbidding him to run for office.
They all just agreed that it isn't a State decision; which, in all fairness, is understandable.
Had these states not applied this pressure, the Court would not have had the issue before them.
So what they said is, Trump can still be held accountable to 14A if the appropriate body acts to enforce it: Congress.