The World Economic Forum has never been good at crystal-ball gazing. In early 2007, it was smug and complacent even as the financial storm clouds gathered. Last year, there was a strong sense that the crisis was over, an optimism swiftly dashed by a combination of Ukraine, Islamic State and renewed stagnation in the eurozone.

The mood this year was downbeat, a lot more cautious. Perhaps excessively so. The open-ended €60bn (£44.8bn) a month asset-purchase scheme announced by the European Central Bank is unlikely to prove a game changer, but it will have an impact on activity. Plunging oil prices will mean consumers have more money left over after they have paid the energy bills and filled up the car. Cheaper crude is already starting to feed through into forward-looking business surveys.

In the US and the UK, the weakness of inflation means that the Federal Reserve and the Bank of England will delay raising interest rates. The era of cheap money is into its seventh year. For all these reasons, 2015 could be a stronger year for the global economy than current forecasts suggest.

Are there downside risks? Plenty of them, naturally. Falling oil prices create losers as well as winners, and Russia is not the only big producing country that looks vulnerable. It will be worth keeping an eye on Nigeria and Venezuela over the coming months.

Things could cut up rough in Europe. Whatever the outcome of its election, Greece is going to require more debt relief. The Germans, unhappy at what Mario Draghi is doing at the ECB, are unlikely to be in a mood to grant it.

In Davos, the assumption was that even if the leftwing Syriza party wins the Greek election, its leader Alexis Tsipras, will quickly drop his hardline rhetoric and broadly continue with the current economic policy.

But he might not, which raises two possibilities. One is that Greece defaults and leaves the euro, and that the economic disaster ensues. The other is that Greece leaves and thrives. That would be even more disruptive. Despite the noises coming out of Berlin, there was little support for Angela Merkel’s stance in Davos. The view was that the ECB was doing what it had to do to hit its inflation target, that the attempt by Germany to link monetary easing with structural reform was misguided, and that Tsipras is right when he says Greece’s debts are unpayable.

These obvious risks were much discussed in Davos. As were three longer-term challenges. The first is the need to ensure that 2015 ends with a new set of ambitious sustainable development goals and a way of funding them so that they are met. Jim Kim, the president of the World Bank, was making this point in Davos.

The second challenge is the environment. One concern among environmentalists is that the collapse in the oil price will make renewable energy relatively more expensive and will therefore fatally delay the shift from a dependency on fossil fuels.

It might not. Lord Stern thinks the lower oil price is an opportunity as well as a threat, because it allows government to phase out fossil fuel subsidies without hurting consumers in their pockets. What’s more, he is pressing for government to take advantage of ultra-low borrowing costs and advances in new and cheaper technology to create cleaner cities. By the Paris conference at the end of the year, it will be clear whether Stern’s compelling argument is being heeded.

Finally, there’s the whole question of secular stagnation, the apparent inability of the advanced countries to shake off the effects of the financial crisis and deep recession of 2007-09. The former US Treasury secretary Larry Summers says the west is turning Japanese, with low growth, low inflation and low productivity the norm.

After six years of low interest rates and quantitative easing, the obvious conclusion is that the threat of secular stagnation is not going to be tackled by macroeconomic measures alone. Structural reform is needed. But not the sort of structural reform that involves pay cuts, a weakening of collective bargaining and austerity. That will increase rather than decrease the risk of secular stagnation.

Instead, structural reform has to address the root cause of secular stagnation: inequality. The standard view of the crisis is that it was caused by greedy banks. It wasn’t. Nor was it the result of impersonal global forces over which policy makers had no control.

What happened was this. In phase 1 decisions were taken that changed the balance of power between labour and capital. Trade union power was curbed, financial markets were liberalised, taxes were cut for those on higher incomes.

In phase 2 businesses took advantage of the spread of the market economy to China and India to shift production to lower-cost countries. This helped reduce poverty in Asia and led to higher profitability for multinational companies but led to imbalances in the global economy. China, Japan and Germany exported more than they imported, and so ran huge trade surpluses. The US and Britain consumed more than they produced and so ran huge trade deficits. Banks were perfectly willing to lend consumers the money to live beyond their means. The system was kept going on tick.

Attempts have been made to address some of these weaknesses since the crisis. Banks have been forced to hold more capital and low interest rates have eased the debt burden on consumers. But the repair job is incomplete. As Mark Carney noted in Davos on Saturday, risk in the financial system has migrated from the traditional banks to the hedge funds of the shadow banking sector. Growth projections rely on consumers being prepared to take on more debt.

Nothing, though, has been done to reduce inequality. Indeed, the trend has been in the opposite direction. In both Europe and a lesser extent the US, investment has fallen as a share of national output, harming productivity growth. Jobs have been created, but far too many of them have been low paid. What’s more, QE has done far more to boost financial assets than it has to boost real economic activity. The real beneficiaries of central bank activism have been the undeserving rich.

As usual, there was plenty of hand-wringing in Davos about the need to do something to reverse this trend. As usual, there was a failure to contemplate what this might mean, apart from the motherhood and apple pie of education, training and skills. It actually means a repudiation of austerity. It means the willingness of governments to take advantage of low interest rates to borrow for public investment. It means closing tax loopholes and tax havens so that governments can afford to invest more in education and training. And it means stronger trade unions. Business leaders have a choice. Understand that less inequality equals stronger, less debt-dependent growth. Or watch as secular stagnation takes hold.