Put 2 economists in a room and you get 3 opinions.
Since 1815, effectively the modern economic era, there have been multiple economic crisises in major power developed nations and/or states. Several of them rose to the level of existential crisises, most notably the 1930s in the US, UK, Germany, and France, the 1970s energy crisis, the 1980s USSR, and 2008 in general.
Each one of those was different, but they show that there are effective limits to economic theory, at which point all sorts of things can happen.
My personal view is that the post 1945 productivity boom was the result of the world, transitioning from the coal driven ( such as UK and Germany) Second Industrial Revolution model to the hydrocarbon economy, particularly with portable internal combustion engines fueled by oil products, plastics from oil products, and synethetic fertilizers from the maturing chemical industry. These effects were masked during the 30s and 40s because of the economic, political, and military situations.
However, as noted earlier ITT, this also had serious inflationary pressures, which were pushed elsewhere as long as politically possible, before ripping apart the world hyperpower's economy in the 70s and 80s.