Thought for the day comes from the book of Luke: “There will be more joy in heaven over one sinner who repents than over 99 righteous ones who do not need to repent.” Might we place in the repenting category the UK boss of bankers Santander, the former chairs of Marks & Spencer and HSBC, and the heads of the Confederation of British Industry, Barclays and Lloyds?

All have now, in one way or another, questioned the viability of capitalism as we currently practise it, blaming management greed, tax evasion and other corporate sins. The Financial Times reports today that Shriti Vadera – once Gordon Brown’s eyes and ears at the Treasury, now head of Santander – told a conference that “the underlying promise of western capitalist economies – that a rising tide lifts all boats – has been broken”; a “better model” is needed.

Robert Swannell, once of M&S, said capitalism has “lost its way”, with companies and investors preoccupied by short-termism. Carolyn Fairbairn, of the CBI, spoke of capitalism’s wrong turnings. “The financial crash, a fixation on shareholder value at the expense of purpose, and the toxic issues of … payment of tax and executive pay stand in the way of redemption,” she said.

These sentiments aren’t new. Reflecting on the financial crash, Brexit and the rise of Donald Trump on the back of America’s left-behinds, many have said much the same. But still it is a moment to hear the stewards of the capitalist system admit that the game, as it has been ruinously played, is up.

But don’t be fooled. Don’t assume that – having at last identified for themselves the problem – they can be relied on to fix it. One should not be cynical. They may really want to, motivated by public-spiritedness or a sense of self-preservation. But the currents of capitalism make it virtually impossible for those who practise it to swim against the tide. Capitalism cannot self-regulate. It needs checks and balances. Those with an interest in checking its excesses need the muscle that would allow them to do so.

Don’t assume that - having at last identified for themselves the problem – they can be relied on to fix it

It’s heartening to witness mea culpa. But the only thing that can truly shape a better capitalism is better representation of people in politics and the workplace: a recognition that the private sector isn’t inherently superior, a new mindset that says there are holy grails other than growth to be pursued.

And above all, as a counterpoint to the devil-may-care capitalism the titans themselves now worry about, we truly need strong, responsible and confident unions as players again. That balance exists in many countries. Some of them form part of the Europe from which we are now cutting ourselves adrift. Before we do, it might pay us to look and learn.

• Hugh Muir is a Guardian columnist