[tete]

I'd say vendor lock-ins and mobile killed P2P.

With people replacing more and more laptop and desktop usage the platforms are Android and iOS. On both of these you essentially have to pay to release software, on top of that people more frequently have to pay for traffic, which oftentimes is in some for of ISP NAT, which might mean no or only certain incoming connections.

I think these platforms are the biggest inhibitor for P2P and actually also new technologies, because they are extremely constrained in what you can do compared to a typical desktop OS/environment.