Any time the federal government wants to rule on something against what these people want, but which they dont feel would be socially acceptable to let people know they want, the pull out the “leave it to the states” argument. After all, if all the states ought to allow something, then theres no difference between it being allowed by every state and by it being allowed everywhere by the federal government. Theres nothing that is fundamentally moral in one state but immoral in a different state. The only reason why you’d want to “leave it to the states” on something like this is that you actually dont want to allow it, dont think you can currently get it banned at the federal level, but do think some states would do so given the chance.