The 10th Amendment does not allow the States to ignore or violate the Constitution as a whole. But, the problem now is that the Feds are equating a lifestyle choice with an immutable characteristic such as skin color. If this stands, the proponents of most any aberrant sexual behavior will make the same arguments to try to force states to allow said behavior.
Absolutely not. Don't believe the rubbish put out by the Leftists, especially those in government. They're working on the entire Constitution becoming dead letter.
The Constitution is the Law of the Land (Article VI Section 2). If the clause or section or amendment hasn't been validly amended by the process outlined in Article V, then that portion of the Constitution is alive and well. Has there been an amendment that overturns the Tenth Amendment? Of course not because the Tenth Amendment is simply an expression of the implicit presumption of the Constitution, something lovers of big government hate.
But the Constitution only has the force the American People insist. The Constitution is written law but it also needs to be alive in the hearts of Americans. As the Declaration of Independence says, our lives and freedoms are God-given and the Constitution is a miraculous gift from Heaven. But we must fight for what is rightfully ours or the thieves and wolves will steal it which they have been working on doing for a long time.