New Zealand retained the William Webb Ellis Cup with a 34-17 victory against Australia at Twickenham, having ended a 24-year drought without the trophy courtesy of a nerve-jangling 8-7 win over France on home soil four years ago.
The Kiwis also prevailed in the inaugural edition, again beating the French (29-9) in the final, back in 1987.
Rush believes the current crop are the finest XV of all time and their global dominance won't diminish despite a spate of international retirements, with fresh-faced youngsters understandably keen to make their mark now and a historic three-peat fixed firmly in their sights.
"We've lost six of the key guys. Five of them played 100 test matches and Conrad Smith played 94, so that's a lot of experience walking out of the team," the Sevens legends said.
"But, the great thing is that the coaches have known that for a couple of years and they've started working on the next layer of talent.
"Although those boys will have some rough bumps in the road, the expectation won't change. That's what it means to be an All Black. It doesn't matter if you're new or rebuilding, you've still got to win.
"It's pretty unfair now because teams are judged every four years, but that doesn't count in New Zealand; it's basically every game and every year.
"We won't be quite as successful as the last four years, but -- by the time the next Rugby World Cup comes around -- the new guys that will come in next year will have 30, 40 or 50 games under their belts.
"South Africa are losing guys too and the Wallabies will be the same, so it's about the quality of the young guys coming through."
Rush sees Aaron Cruden as the 'front-runner' to replace the ABs' mercurial first-five Dan Carter, while Sam Cane or the 'standout' Ardie Savea are candidates to replace skipper Richie McCaw should he decide to hang up his boots.
Kieran Read is the 'heir apparent' to take the captain's armband if McCaw bows out on a high.
Those changes to the playing personnel are unlikely to have an adverse effect, especially with the culture, ethos and expectation remaining the same in Steve Hansen's squad.
"When you're playing for New Zealand, there's no Plan B. You've got to win when you're playing rugby," Rush added.
"That's tough sometimes because you're not going to win all of the time. That's just how it is, but the expectation for the New Zealand rugby team doesn't change and I guess that's why we've sort of been more consistent than some other teams over the years because that expectation is always there. It's a double-edged sword sometimes."
