The most convincing answer I've come across is from Greg Clark at UC Davis. A long-run process of Malthusian conditions eventually led to significant changes in the human capital stock which enabled the Industrial Revolution. Some notable examples of apparent differences in average traits between Romans and Pre-Industrial England:
Interest rates (risk-free rate around 10-20% in Roman times vs 3% in 1800 England)
Violent tendencies (likely high murder rate and atrocities as entertainment in the Colosseum vs lower murder rate in 1800 England than in modern America)
Literacy/Numeracy (most Romans did not know their exact age and likely could not read vs 70-94% rate of numeracy and ~50% rate of literacy in 1800 England)
Work hours (harder to measure but it looks like people in 1800 England worked about 20% more than people in Medieval England)
The trends noted above have much better data for Medieval England than Ancient Rome, but the direction of travel is quite clear and likely would apply to Ancient Rome. Greg Clark has an entire lecture series on this general topic on Youtube, highly recommended.
The most convincing answer I've come across is from Greg Clark at UC Davis. A long-run process of Malthusian conditions eventually led to significant changes in the human capital stock which enabled the Industrial Revolution. Some notable examples of apparent differences in average traits between Romans and Pre-Industrial England:
The trends noted above have much better data for Medieval England than Ancient Rome, but the direction of travel is quite clear and likely would apply to Ancient Rome. Greg Clark has an entire lecture series on this general topic on Youtube, highly recommended.