Will IPv6 and later IP technologies help see the demise of spam and still allow internet users privacy?

IPV6 has little to do with spam, and almost nothing to do with it's proliferation in specific. IPv6 It has to do with the addressing scheme used for network connectivity. It may cause certain programs used by spammers to be re-written, however that will likely be done quickly and we will see only a slight decrease in spam, if any.