Would you want to do that for 40 years? Better to be a pro bodybuilder where you'll be dead in 20.
The smart guys will go out on their own and leverage themselves by expansion.
From one truck to two, three, etc. with employees billed out at $150-$200/hr.
Obviously, not everyone has the brains, balls and can handle the responsibility and stress to do that so they remain employees.
The one-man show guys will find it tough.
Even as an employee, you can make an adequate living.