I don't know whose life works in this extremely simple way, but it sure isn't mine. I've gone from making good money to being broke to making good money again and everywhere in between in my 35 years on this planet.
These types of things never make any practical sense because they assume I'm going to be working at the same job for the same pay for the next 30 years or so. Maybe that was the norm in the '60s but few people do that anymore.
Saving money is good, no doubt, but if you're concerned about retiring early, you're much better off figuring out how to do it by making more money.