To my understanding, the upstream ends are linked largely thanks to peering, which is based on mutual benefit. At the upstream level, nobody charges other providers because everybody is interacting with everybody- sort of like, "I bought this round, but I know you'll be buying the next" so you don't worry about balancing the books.

Then Netflix comes along, chews up 35% of internet traffic, and basically takes a disproportionate piece of the pie. If I've got everything in my head right, this is against the spirit of how peering is supposed to work, and so it doesn't surprise me if spats start to develop upstream.

If Verizon is unhappy because they have to develop their last-mile network to meet promised speeds, that's Verizon's problem. But if Verizon is unhappy because the upstream is becoming distorted and they are becoming beholden to just one peer (Netflix) instead of an environment of free, balanced exchange- maybe that's not Verizon's problem.