Also, lifespan is longer, so it makes more economic sense to prolong the consumption/invest in yourself phase, since you have a longer period to earn it back AND more capital and tools with which to leverage your work. Someone today could probably earn enough in just 25 years of focused work to cover an 80 year life for them and their family if they wanted to. Not possible when lifespans and wealth lower, and had to work as many of your years as you could.
RE: Why Does It Take Longer for People to 'Grow Up' These Days?