There were many things they failed to do to live up to the greatness embedded in the Constitution, including slavery, child labor, women's rights. But time has resolved many of those shortcomings. Every one of those so-called Christian state constitutions, and there were several, violated the US Constitution with their explicit religious tests. I don't make excuses for the failure of the federal government to protect the rights of its citizens. But it has learned over the years that a government's first duty is to protect the rights of all of its citizens, not just good Christian white male landowners.
Nonsense on stilts.
The Constitution prohibited any religious test for officers of the United States, not for those of the states.
The 1st Amendment prohibited congress from establishing a religion, it made no comment on whether a state could do so.
It wasn't until the post civil war amendments that the bill of rights was applied to state action.