When the Constitution was ratified there was at least one state with an official religion. The SCOTUS would be wrong if they said that a state could not have a state religion just as they were wrong when they said Dred Scot was only property and that the imagined right to privacy in the Constitution prevented states from enacting laws against murdering babies.
What part of "Congress shall make no law..." do you and your hypothetical SCOTUS not understand?
And why do you imagine that our nation's form of government is a judgeocracy or some crap like that and not a Constitutional Republic of several sovereign States? Where did you learn otherwise?
Well, the 14th Amendment prohibition on the state depriving any person of liberty, including 1st Amendment liberty derived from the language beginning "Congress shall make no law...", says your view is wrong. And so the SCOTUS has held for the better part of a century.
I hope you understand the implication of your argument. If "Congress shall make no law..." is the last word (despite later Amendments), then the state in which you reside can pass laws restricting free speech, freedom of the press and free exercise of religion - and there is no Constitutional problem at all with such laws.
That may be the country you want to live in, but it is not mine.