> This literally exists. There's no need for it to be part of the original specification because it's a completely separate concept.

By that token, IPv6 never had to exist at all then, but we know that is completely missing the point.

IPv6 is a privacy nightmare without privacy extensions. It is designed with "a stupid desire to pretend we can boil the ocean".

Close to 3 decades and we are barely scraping 50%: https://stats.labs.apnic.net/ipv6/