The biggest issue is that 30 years ago the odds of getting a tenure track position if you stayed in academia were much higher, and you often didn't need to do a

The biggest issue is that 30 years ago the odds of getting a tenure track position if you stayed in academia were much higher, and you often didn't need to do a postdoc for more than a year or two at that. I'm guessing PhDs were more consistently finished within 5 years back then too. The real problem in this specific instance isn't changes to industry/the economy, it's actually academia that has changed in a bad way.