My understanding is that IPv6 incorporates VPN, making the current VPN technology obsolete.
From what you know about IPv6's implementation of VPN, would it resolve the author's concern's about privacy? For example, a company could set up a VPN for clients. All clients would tunnel encrypted data to the company, turn off all other traffic (ports and addresses), and then access the internet through them. This should take care of privacy concerns. The company could even constantly rotate addresses assigned to each client much as DHCP works today.
In a fully IPv6 home, most items could be set to only interact with other household equipment and access the outside world only through a gateway.
In addition, new IPv6 home routers will probably include some sort of mechanism to handle legacy IPv4 equipment. At a minimum, computers would have both protocols and could be set up as gateways. That in itself would need to be a NAT product between the to versions of IP.