>but "network" itself is an abstract concept. This is incorrect. IPv6 network routing prefixes are not an "abstract" concept. They are effectively the same PII

>but "network" itself is an abstract concept. This is incorrect. IPv6 network routing prefixes are not an "abstract" concept. They are effectively the same PII as an IPv4 address. You can identify a user by their routing prefix, much like you can identify a user by their IPv4 address. All of their devices will have IPv6 addresses from their unique prefix much like all of their devices will have the same unique IPv4 address if they're using NAT.