The funny thing is, it was not explicitly clear at the time of the founding whether things like the First Amendment applied to States at all. After all, the Constitution applied to the Federal Government, and States had their own government....

.... Until after the Civil War, when the 14th amendment was ratified. You might be familiar with the 14th Amendment as it is the one that guarantees birthright citizenship. Well, that's just it's first sentence. The second sentence also guarantees all citizens the rights enumerated in the Constitution, making it clear that the States cannot abridge those rights.

But right now, the plain language of the 14th Amendment is under attack by Conservatives who claim that it all of a sudden does not cover people born here whose parents are not citizens. So as long as today's Conservatives will ignore one part of the 14th Amendment, why not ignore the rest and hope a captured SCOTUS makes it all hunky-dory after the fact!