Earlier quoted context omitted.
The amount of 'free time privilege' required to become a developer is less than the amount of 'privilege' required to become almost any other well paying profession. With software, you need a cheap computer, access to the internet and time to teach yourself. That can cost about $300 and $10/month in many places. With almost anything else you need all of the above plus a college or other formal education. The barrier…
You need the time to teach yourself. There are hard limits on the amount of physical and mental work a person can do, especially if the mental work requires significant concentration. I don't see you taking account of that at all.
Also, don't underestimate the value of an educational environment. You can spend a lot of time banging your head against the wall if you don't have an effective way to reach out for help. A mailing list or IRC channel is only useful if you have the skill and focus to compose your question coherently.