I couldn't find anything about it on Mr. Turnbull's web site, but there were several news items, such as: Turnbull seeks lifelong 'pigeonholes' for all, ABC News Online, September 9, 2005. 10:50am (AEST):
Federal Liberal MP Malcolm Turnbull has called for the Government to give every Australian their own email address for life.
The emails would be used by Government agencies to keep in touch with people, or they could be used by long-lost friends.
He has suggested the address could be: email@example.com. ...
I recall discussing something like this ten years ago back in the heady days when the Internet was going to be free.