Is that even true on populist and financial crises?
Yes. It appears that Manuel Funke, Moritz Schularick and Christoph Trebesch may not have been as conscientious as they could have been about reviewing prior literature.
Edit: post changed the paper linked, but generally my point stands.
I would describe it as the "conventional wisdom" account of how populism functions e.g. the Great Depression is described as a necessary context for Hitler's popularism to be effective i.e. economic grievance fuels anti-establishment / anti-elite narratives. You get the Occupy Wallstreet movement after a crash/recession, not during a boom.