What protection? What privacy? Smoke and mirrors, mostly.
NAT is a firewall with extra steps. IPv6 reduces complexity. Privacy (illusion of it, anyway, just like in ipv4 NAT) is handled by private addresses.
…and if you really want to, NAT for ipv6 just works.
It's the illusion of a firewall too.
NAT changes the apparent destination address of a connection, it doesn't filter them. If a connection arrives with the destination address already set to one of your machines, NAT won't prevent it.