I didn't know 'Hypergiant' and 'off-net' were the correct academic terms, but if I understand correctly, this is basically about eg Netflix installing a netflix content streaming server at your ISP. It seems to make perfect sense for them to do so, especially for relatively static content, IMHO.
It's a neat trick to scan the certificates to out these servers, but I'm not really convinced these 'deployments change the structure of the internet'.
I’d argue private caches and peering have changed the “structure of the internet”. Previously such investments would have been made by large telco and “backbone” providers instead, with the traffic originator footing the bill. The private CDN model is clearly more efficient than paying the likes of Verizon to lay more fiber.
It's a neat trick to scan the certificates to out these servers, but I'm not really convinced these 'deployments change the structure of the internet'.