The one thing all the predictors mentioned in the article seem to have in common is that they're all efforts by the financial industry to wring more profit out

The one thing all the predictors mentioned in the article seem to have in common is that they're all efforts by the financial industry to wring more profit out of the real economy - i.e. the one that produces goods and services of more tangible value than numbers on a balance sheet. Without proper regulation, competing on the basis of investment returns inevitably creates a race to take ever greater real risks, independently of the risks as portrayed to investors, and employ ever more sophisticated tactics to obscure the difference. That's why I and many others who've lived through more than one economic cycle know that when the ratio of finance-industry profits to real productivity takes a sharp uptick it's time to run for cover.