Comment by jameslk

The steel man of your argument sounds like:

If we let states have more power, they may enact good or bad policies that others cannot as easily enjoy or escape because of their financial or family standings prevent them from moving. National policies allow everyone to benefit from good policies.

While this is true, the reality frequently seems to be that no bold policy is made or maintained due to polarization or perceived risk. Isolating policies to places willing to try them out is a better outcome. If the policy seems valuable, more states will adopt it

And if you have bad policies nationally, it’s even harder for those less privileged to escape them due to things like immigration laws, costs, language barrier, xenophobia, etc