Why? It was designed and implemented by competent people and continues to work today.
If you have a dedicated IPv4 address, those behind NAT and CGNAT face significant throttling and false positive blocking. It's been made worse by scraper botnets.
https://en.wikipedia.org/wiki/End-to-end_principle
If you have a dedicated IPv4 address, those behind NAT and CGNAT face significant throttling and false positive blocking. It's been made worse by scraper botnets.