It'll happen over overlay networks for other reasons, like the Internet being a dark forest hellscape where anything public gets attacked.
Overlay networks are probably the future. IPv6 lets them be fully P2P and more decentralized.
Edit: one more piece of detail about upstream bandwidth at home. 30-40mbps/sec up is a DOCSIS cable system limit. That's the only reason for that really. Cable was never designed to be bidirectional and the stuff they do with modulation to get shared upstream is heroic. It's also related to why cablemodems tend to use a lot of power. They have to blast spread spectrum pretty loud to get it to the CO. Fiber will save energy.
Overlay networks are probably the future. IPv6 lets them be fully P2P and more decentralized.
Edit: one more piece of detail about upstream bandwidth at home. 30-40mbps/sec up is a DOCSIS cable system limit. That's the only reason for that really. Cable was never designed to be bidirectional and the stuff they do with modulation to get shared upstream is heroic. It's also related to why cablemodems tend to use a lot of power. They have to blast spread spectrum pretty loud to get it to the CO. Fiber will save energy.