Re: "Peer"?
"I can't imagine YouTube's upstream bandwidth requirement being within an order of magnitude of the downstream..."
Now, but every ISP on Earth's subscribers want access to Youtube. Explain to me what about the camera stream/HFT supplier's network appeals to any but a tiny, tiny subset of any ISP's subscribers?
Peering doesn't have to be about equal amounts of traffic in either direction, it can simply be that it makes rational business sense to freely interconnect due to subscriber demand. I don't see how there is massive subscriber demand for the complainant's services, or that the complainant is offering anything that puts them on remotely equal footing. They seem - at least at first glance - to just want cheap bandwidth for lashing together equipment they have at different IXes.