There's a fundamental difference between an ISP and an edge provider. The service provider is like a system of roads whereas the edge providers are destinations

There's a fundamental difference between an ISP and an edge provider. The service provider is like a system of roads whereas the edge providers are destinations. As long as the roads are free, it should be fairly easy to buy a plot of land and build your own destination. However, if the road company won't allow you access, it stops being feasible. Now in this analogy, large edge providers are campuses with internal roads that they control and many entrances and exits. They too can become a problem when they grow large enough. So therefore, I would think keeping the road system neutral insofar as the connections it allows would be the first priority. Making sure edge providers don't subvert the system either by growing too large or by organizing to control the main system of roads would be of similar but lesser importance. Moreover, if the main roads aren't neutral, there's no reason to make campus roads neutral.