So in the end Jack did not kill the 15 giants. But still the Rugby World Cup had a different kind of fairytale finish. Siya Kolisi, South Africa’s first black captain, a kid from a township outside Port Elizabeth, led his team to a famous victory. And a team that once epitomised the apartheid regime was reborn, at last, as one offering the promise of togetherness. It was not long ago that the Springboks were jeered by black South Africans. Now they are being cheered by them. They have made good on Nelson Mandela’s words from 1995. “Sport has the power to unite people in a way that little else does,” Mandela said, “Sport can create hope where once there was despair.”

We should not garnish it any more than that. If anything, this may be the moment to offer a timely reminder that we should not overreach or strain to explain the significance of all this. South Africa’s coach, Rassie Erasmus, was absolutely clear about the limits of what his team had achieved. The World Cup final had bought his country 80 minutes of togetherness, Erasmus said, and a couple of happy hours after the match when people back home had put aside their differences. Nothing more than that. The social problems he and Kolisi spoke so openly about this week will not be fixed by this victory. But it will give some succour and a hint, too, of what is possible.

England’s World Cup final defeat to South Africa proves Warren Gatland was right | Nick Evans Read more

There is also hope there for England. This was all at their expense, but they are a young team, the youngest to play in a World Cup final with 25 twenty-somethings in their squad of 32. And what they have achieved these last six weeks has to be set against the way they embarrassed themselves, and everyone else, in 2011 and 2015. England were never, have never been, better than they were on the weekend they beat the unbeatable All Blacks. It may turn out, when they finish their debrief, that they were still suffering from the hangover of that when they played South Africa.

Play Video 1:11 South Africa captain Siya Kolisi: 'we can achieve anything if we work together' – video

They would not be the first. New Zealand have lost four World Cup knock-out matches in the last 20 years now. None of the teams who beat them went on to win the final. It is one thing to persuade yourself the fabled All Black aura does not make any difference in the week before playing them but another really to believe it the week after, too, when you are sure you are already on top of the world. There are always new lessons, then, even for a wily old dog like Eddie Jones. As one of his young standout performers, Sam Underhill, said when he was asked if he had heard of the theory that you have to lose a World Cup final before you learn how to win one: “No, but I’m a fan of it now”.

Even the English may agree that South Africa’s victory was a fitting way to finish a tournament that was, after all, about opening the game to new audiences. It is easy to forget in the wash of it all what a risk World Rugby took by bringing their marquee tournament to Japan, where the game is – or was – a minority sport. There has been nothing quite like it since Fifa decided to hold the 1994 football World Cup in the US. And it has paid off. They filled almost every seat in every stadium and at the tournament’s peak won an audience of 54.8m TV viewers in Japan alone.

'We are a special country': South Africa hopes World Cup win can bring unity Read more

Play Video Japan 'probably the greatest' tournament, says World Rugby chief Beaumont – video

That was during Japan’s game against Scotland at the end of the pool stages. It was one of those matches which meant more than can be conveyed in facts and figures like that, when the sport became about something much larger and more important than itself. It was the day after typhoon Hagibis had blown through and, around the country, they were still reckoning the damage. The official death toll was 24 when the match started, 28 when it finished. Days later it finally reached 89. Some of those deaths were just miles up the highway from the stadium.

What was that match but a gesture of pride and defiance and togetherness? They were pumping floodwater out of the changing rooms on the morning of the game. One could hear the plain truth in Mandela’s words then. And one could hear it again in the little town of Kamaishi, the smallest place to host a World Cup match, where they had built their new stadium on the site of the school that was swept away in the tsunami in 2011. There never was a town that seemed as happy to be hosting a match. It was, the manager of the local rugby team said, their way of thanking the world for its support after the disaster.

They never did get to play the second game that was scheduled there. It was one of the three matches cancelled because of the typhoon. It would have been the biggest fixture of the tournament for the two teams who were due to play, Namibia and Canada. But instead they got on with helping the people who lived there clear up the damage. Rugby loves to talk about its values and there they were again for everyone to see in the footage of the Canadian players shovelling mud off the roads.

Facebook Twitter Pinterest Canada team members clean a road in Kamaishi following the cancellation their match against Namibia because of Typhoon Hagibis. Photograph: 横山純太郎/AP

It was a timely reminder of the best of the game because there was some of the worst on show too, in the backstage bickering between the unions about who was to blame for the cancelled matches. It was a flash of the sport’s narrow-minded side. If the World Cup offered a glimpse of what the game might become, it also showed some of what is holding it back. In Europe the game is being taken over, piece by piece, by the private equity firm CVC Capital Partners, who were recently accused of “raping the sport” of F1. Let us see how those traditional values and this newfound drive to develop the game, this desire to prioritise player welfare, hold up in partnership with a firm whose biggest worry is the bottom line.

In many ways the game has changed these last few weeks. This tournament could be the beginning of something. And in many others the game remains the same. It could also be its end.