While laws and treaties must operate within certain parameters outlined by the Constitution states are not constrained by the Constituion if they want to extend more protections than the Constitution provides.
If the founders were of a mind that the Constitution was the "Supreme Law of the Land" it would have been quite easy to confine Artilce 6, Clause 2 to exactly that. They didn't and they didn't for a reason.
So when you say the Constitution is the Supreme Law of the Land (period), you contradict the Constitution.
But that doesn't surprise me, there are so many people who simply ignore the plain wording of the Constitution it has lost its meaning.
The politicians have made a systematic and concerted effort to replace the commonly understood meaning of much of it. The Founder's concepts of things like "the general welfare" and "regulating commerce among the several states" have become so twisted from thier original meaning that trying to put them into the context of the Constitution as a whole returns gibberish.
But that is what they wrote! They used the word "supreme," which means highest, no other meaning can be applied here. “And the Judges in every State shall be bound thereby [i.e. To uphold the Federal Constitution], any Thing in the Constitution [the states' constitutions, not the Federal as is clear from the next few words] or Laws of any State to the Contrary notwithstanding." This all means "In spite of, the Constitution, Treaties , or Laws of any state." Thus the Federal Constitution trumps literally everything.
But that doesn't surprise me, there are so many people who simply ignore the plain wording of the Constitution it has lost its meaning.
I suggest you look up the word notwithstanding, In the context it's pretty clear to me.