Allowing states to regulate subscriptions is different than slavery.
In particular, states shouldn’t have the right to restrict travel. If the slaves had free travel they would just leave for northern states. If people are able to leave to other states (even if it means rebuilding their life), plenty of bad state laws are OK because those affected will do so.
The 14th amendment says no state shall deprive you of your life or liberty, not a minimum of one state, should you have have the funds and will to move there.
In particular, states shouldn’t have the right to restrict travel. If the slaves had free travel they would just leave for northern states. If people are able to leave to other states (even if it means rebuilding their life), plenty of bad state laws are OK because those affected will do so.