I honestly think the fault here is not technical, it's ISPs.

Between the RIAA/MPAA breathing down their necks about piracy, and the realization they could make a mint charging inflated "business rates" than letting you do what you wanted with your own damn internet connection, shit got locked up tight so fast no one even noticed.

It's not NAT that's why my ISP is blocking half the protocols on the Internet. Why every ISP I've had for the last decade has blocked outgoing HTTP. Why I'd need to us a fucking VPN tunnel just to get SSH to my home computer. It's greed.

It's the forgotten front of the net neutrality fight, and it's gone almost entirely ignored. We don't have the right to our own outgoing traffic anymore, and this has been the case for far longer than IP allocation has been an issue.