I think this conflates arrangements that retailers/shippers make with each other and the agreements that consumers have with their own network supplier.
a) As a customer of a retailer that ships physical packages, my contract is with the retailer. They promise to deliver on a certain date, or they yell at the shipper.
b) As an *network subscriber*, my contract/agreement is with my (cable/DSL/satellite/mobile) ISP. I pay them to deliver my bits - without any discussion of where they come from. Most of these agreements don't provide much of a service level. But I still have the understanding that *all* data coming to/from me will have substantially the rate, latency, and packet loss that is advertised.
Specifically, I have the expectation that data from two streams (say, one from a Binge On participant, one from an unsubsidized source like an Ubuntu ISO download) should arrive with substantially the same rate, latency and packet loss.
I can then remain ignorant/uninvolved with whether any source wants to use CDNs, or to subsidize a subscriber's data plan, or make any other arrangement between the data source and the intervening providers. As long as data is arriving at the contracted rate, I am getting what I paid for.
Isn't that a useful and testable basis for understanding Net Neutrality? Doesn't this address (at least part of) the argument about guaranteeing equal access to all content whether subsidized or not?