Theoretically yes but if your ISP assigns your home a /64 you can use 2^64 different addresses to access the internet.
This still doesn’t protect your privacy because your ISP knows what prefix they gave you and will likely provide that to the authorities if you broke the law while using that address. Just like they would even if you used NAT and ipv4 so I don’t get where the parent comment thinks that is protecting their privacy at all.
Plausible deniability. My NAT and DHCP leases can be shortened, and not logged. At best you know something came from my network, and I may have many users on my network. For nodes, VPN, etc...
IP's address Internet endpoints, not people using them, yet States, prosecutors, and law enforcement regularly try to create the illusion that an IP has anything to do with who uses something.
IPv6 makes that temptation worse. IPv4 forces you to realize IP's can be ambiguous. IPv6, through having more addresses than people on Earth, checks off the Institutional checkbox for "raw material to contribute to a UUID identity scheme". Just look at China's proposals for a more governable international Telecom network, and the intention to use device persistent addressing as a control mechanism becomes obvious.
Where IPv4 creates enough decentralization and localized namespace unscrambling to provide enough friction via statefulness to thwart these types of efforts, I'm not at all confident IPv6 will do the same. I believe it is just what the Doctor ordered for laying the foundation of coupling IP's and net addresses in the minds of the masses to personal identifiers.
Which is not by any stretch the way we want things to go.
If your location is assigned a /48 you can then set up over 65,000 subnets with 2^64 possible endpoints in each.
My iPhone spoofs the MAC address each time it connects to WiFi, so support for changing your /64 is not going to be a challenge even with consumer devices. Whether we lose this ability or not is another question (but they could easily make the same requirements of “hard device uuid” on IPv4 if they wanted. These are laws and regulations after all, not technical limitations).
If anything IPv6 gives you an even greater amount of plausible deniability because like you said you could be running a vpn with a billion different devices connecting to it.
IPv6 just means your laptop could have an internet routable IP associated with it. You can easily change to one of the billions upon billions of possible addresses that your assigned prefix will give you (just like you could have something like 10.0.0.0/8 with millions and millions of addresses behind your internet routable IPv4 address. Your ISP will turn you over all the same if the authorities ask who that address belongs to.
