"For a lot of guys like myself, who come from big families, from low socio-economic backgrounds, the chance to change your family's life is pretty overwhelming. It's not something you should take lightly and sometimes the jersey is not enough for a better life. It is special, the experiences you have are pretty surreal, but down the track those things don't pay for a roof over your head."
As virtually all rugby followers in New Zealand have been quick to point out, this is the perspective of a fringe All Black. Sopoaga played 16 tests but only started two – his first (a triumph against South Africa where he looked a world-beater) and his last (a loss to the Wallabies where his star dimmed).
If there was fault with the All Black coaching staff, it was in not giving him more starts, presumably a mistake they will not repeat with Damian McKenzie and Richie Mounga.
In the history of sport – indeed, the history of employment – few careers have been enhanced by being permanent second fiddle. There has to be a sense of succession.
That's the thing about the All Black jersey. Every All Black I have ever met over the years was never satisfied with selection. To a man, having gained the jersey, they all wanted to be a great All Black.
Sopoaga is right, rugby isn't forever. But being a great All Black is.
Look at Buck Shelford. He will always be remembered as a great All Black for his from-the-front leadership, physical prowess and manifestation of the New Zealand rugby psyche. Zinzan Brooke, another great No. 8, played for the All Blacks for 10 years before heading to Harlequins 20 years ago.
Victor Vito or Rodney So'oialo? Impressive All Black CVs, yes, but greats?
Dan Carter went to Europe with his career well and truly on the fade. He may not have enhanced his reputation there – but his greatness was assured before he stepped on the plane. Sopoaga? Not so much.
The quest for greatness is powerful motivation still. Money talks, yes, but most sportspeople are possessed of a strong competitive instinct; being the best in the world often trumps cash though the reality is the big paydays tend to follow.
There's also the emotional side – yes, emotional – to consider. Modern All Black teams, and especially this one, have bonded like no other. Rugby has always had an 'us and them against the world' dimension of team but these All Blacks have taken matters much further.
Did you see TJ Perenara hongi Te Toiroa Tahuriorangi when the latter made his All Black debut against the Pumas?
It was a sign of the big difference between the All Blacks and the rest of the rugby planet.
This wasn't just the public 'go well, mate' we are accustomed to seeing in rugby teams round the world when the bench is called to action.
This was Perenara welcoming a teammate who could conceivably knock him out of a World Cup place next year. Doesn't matter. The All Blacks are a club, a culture, a calling; they know it takes 23 to win, not 15, and they have genuinely embraced the fact they are colleagues and competitors.
Even more, they are representative of the diversity that is modern New Zealand; precious few other international rugby teams can point to that strong cultural underpinning of their rugby base.
Having said all that, next year's World Cup will be interesting. If the All Blacks win and do the three-peat, you wonder what there is left to achieve and if the players' focus will stray. Why hang around for the next World Cup if it's a case of been there, done that? Many will go; it's the next crop we have to worry about.
Maybe World Rugby's tweaked international calendar will bring some of the urgency and anticipation back to test matches rather than the largely bland fodder we have right now but…don't hold your breath. We are handcuffed by the broadcasting money.
In time, eventually, Sopoaga will likely be right. The money may overtake the mana. It's the way of the world.
It's why Hansen made his hugely unpopular approach to the government about funding the All Black "brand". It looms in our future like climate change, largely a question of when.
But Sopoaga is in Britain not because of some money-based trend which has seen Charles Piutau, Steven Luatua, Aaron Cruden, Julian Savea and Malikai Fekitoa, among many others, head there. He, like them, is there because his All Black time had either run out or been threatened.