We evaluated QUIC (and many other approaches). Turns out it's a lot harder than you might think to move traffic at high speed across the world, over residential-grade internet, and not drain your battery.
If it's truly p2p, some relay would be there in case the client cannot be reached through NAT. Not sure how they would bear the cost of the bandwidth for unlimited transfers in that case
We evaluated QUIC (and many other approaches). Turns out it's a lot harder than you might think to move traffic at high speed across the world, over residential-grade internet, and not drain your battery.