Very simply.
Understand that much of the book is dated in that America's economy is still dependent on heavy industry.
A mind set has taken hold of government, the private sector, business in general, that unemployment must be kept down. Therefore if one business is run well, successfully uses innovation, thinks outside the box, it is immediately beset by the Feds (directly and through the press), to surrender that which gives that company it's edge to it's competitors so that those competitors will not go out of business and therefore lay people off. The original "too big to fail".
After many examples of this political policy at work, it becomes apparent that a movement has formed among the successful businessmen and innovators, to drop out and play by the politically correct rules no more.
Some of those who have dropped out go to a remote location and live by the rules that make sense to them. Others stay in the world but they work simple jobs for an hourly rate. They do not share their ability with the society that has painted a target on their backs.
Very basic here. Maybe others will help.
Where were you guys when we had our FReeper Book Club on Atlas Shrugged? We could have used you.