There are many reasons other than commercial motive that have eroded the P2P nature of the internet. The single most prominent is security. Improved network har

There are many reasons other than commercial motive that have eroded the P2P nature of the internet. The single most prominent is security. Improved network hardening practices by OS vendors have mostly eliminated the historic problem that computers directly accessible to the internet were quickly compromised (SMB on Windows hosts used to be a huge problem this way), but for years in the late '90s to early '00s directly connecting computers to the internet was considered a very problematic practice due to the number of worms. The more durable problem has been DOS. Home networks are, for structural reasons, extremely vulnerable to denial of service attacks and it's difficult to fix that. The best way to fix it is to be extremely conservative with inbound connections by dropping all of them, and indeed that's what home networks do. For many years NAT was frequently described first as a security feature, although its security benefits were purely incidental. DOS attacks on home networks remain surprisingly common in certain circles such as multiplayer videogames, and have resulted in a climate in which multiplayer videogames are expected to actively conceal the network identity of other participants. Yes, this is basically all an accident of history, but so is everything else about computing. There's no real sense in which the original "network of peers" IP concept has been successful since IP spread beyond the realm of the National Science Foundation. It is possible to build systems which are far more resistant to these problems but it's difficult to begin with, and on top of that adoption would require turning the battleship that is the internet around. We're sort of stuck with the situation we found ourselves in, which is that we build peer-to-peer system by piling a few hacks on top of IP to enable peer-to-peer application layer usage.