This particular GOP CYA talking point is a dog that just ain't gonna hunt...at least with those who reference fundamental human rights as their political and legal compass.
Well I'm not GOP so I don't care what 'talking points' they choose to use or not. The only things that guide me are a strong belief in Christ, fundamental human rights, and the limitations as outlined in the Constitution of these United States. Congress had no right nor position to involve themselves in a simple guardianship case. Justice Scalia in the Cruzan decision was clear and Madison was even clearer in Federalist #45
The Constitution applies in every case.
You are vividly demonstrating the problem. Our courts and our elected officials are IGNORING the Constitution.
You, and they, are straining out a gnat and swallowing a camel.