Oh. That's interesting...
I've never thought of giving the states control like that... I definitely can see how smaller industry entrants could thrive in individual states... and I guess to a degree the US already has that with several states/cities banning ridesharing apps for example.
I guess the potential unintended consequences it could make the US less efficient for industry that gets economies of scale from operating nationally... a railroad company might get all the approvals to run East to West, build all the infrastructure, and then a competitor gets them banned in a middle state which disrupts the entire business case.
Incumbents might have an advantage because they have the resources to lobby 50 states whereas a new entrant wouldn't have the resources to compete.
I know that monopolies and oligopolies are the ideal scenario for corporations, and it's hard to think through all the consequences to see if individual state laws would help or hinder that process... I think I'll have to sit with it a while... I imagine industries would be affected very differently.