I doubt this would be either healthy or productive for most people.
The same could be said of start-up founders, which was the point.
But you can re-do the math at 40 hours a week if you like:
40 hours * 50 weeks * $200/hr = $400,000 / 52 weeks @ $1,000 per week = 7.69 years to do what you want.
And again, we're only talking about a year. Spend a year killing yourself, and then spend the next 5 on the beach or climbing Everest or writing a novel.