One practical concern is that it's a lot easier for a state to implement something like single-payer health care if they can pay for it through state taxes that

One practical concern is that it's a lot easier for a state to implement something like single-payer health care if they can pay for it through state taxes that are exempt from federal taxes. Otherwise, they're competing with employer-provided health insurance, which is already tax-exempt. That gives employer-provided insurance a huge artificial advantage and makes single-payer a lot more expensive in comparison.