Internet centralization and the original sin of NAT

Network address translation (NAT), introduced in RFC 1631 (1994) to mitigate IP address depletion and routing scaling, lets multiple devices share a single public IP by rewriting packet headers, but it blocks inbound connections unless workarounds like port forwarding are configured. Port forwarding maps a specific public port to an internal address, yet only one device can use a given public IP-port pair, limiting on-prem hosting especially behind carrier-grade NAT.