This option is already open to those who want it.
work hard, save enough, and live off the interest. there's no timetable on that any more than what you put on it.
I'll point out that most folks won't produce 2x as much working 80-100 hours/week as they do working 4-50 hours week.
find someone to marry? although the statistics are shifting, odds are a lot more slim at 40+ than if you had the time to look around earlier.
play some sports? have some sex? hike the grand canyon? unlikely, as your body also deteriorates with age. if only you had the time to do some of that earlier.
have kids? sperm count and quality drops drastically across your 30's.
spend time with your friends? what friends? working the 80+ hour weeks means you probably didn't have much of a social life, and therefore don't keep many friends. it might be a good time to try to look for some, but most people in their 40's are now very busy with their own lives -- kids and bigger job titles means less free time.
i could go on, but i feel you get my point. time is money, and older people would (and do attempt to) pay huge sums to regain their youth.
2) Lawyers and doctors frequently work 80-100 hours a week. The amount of productive output is not 2x as much as the 40 hour week; due to fatigue and stress, the productive output only averages out to about 150% more work...in other words, a 25% loss in productivity as compared to just working 2 40 hour weeks.
3) The stress of working 80-100 hour work weeks kills the body good. Literally. It easily ages the body 2-3 years for every year on that sort of schedule. That's why all our presidents have gray hair when they retire.
4) The pyramid scheme: younger generations would have to work even longer to pay for the retirement costs of the retired. People live an average of 25-35 years (depending on sex and race) after 40. So you've made the already unsustainable equation (which sets the retirement date for federal benefits so that only 1/2 of all adults are expected to live past the eligibility date) even worse.
5) France. Enough said.
No, because someone working 40 hours a week has a large set of problems they can't solve -- e.g. anything that takes 160 man-hours to do and needs to be finished in two weeks. Someone who works insanely hard is going to be first to finish a lot of stuff, and the prize for first place can be enough to justify the cost.