The powers referred to in the Tenth Amendment are legitimate powers.
Not illegitimate powers.
Like the federal government, the state governments have no legitimate power to redefine something that God and nature defined from the very beginning.
All they have is the DUTY to protect marriage, since it is the fundamental building block of families, or communities, of society, of civilization, of self-government, and even of the economy. That’s it.
You and I may know it’s fundamental, as God says so in the Bible ... but I don’t believe it exists in the law, as in the U.S. Constitution.
HOWEVER, the people of this country can put it in the U.S. Constitution by the right they have of inserting a Constitutional Amendment. I would advise that route in order to solve all the wrangling over the issue.