The US does indeed have tons of opportunity, I'm a high school dropout, who is now an engineer. Thats an American success story. But I'm luckier than most because I got real lucky in the intelligence department. For a long time, I thought I was an average guy, no smarter than anyone else, then I went out and did complex system design, and then had to write the training material and train the users when I was done, and only then I could see something I hadn't before. I'm frankly smarter than half of the population (and so are basically 100% of the people who use hacker news). People like us will find some form of opportunity when there isn't any obviously available.
I'll rebut your answers:
Example 1: to make use of that free MIT education, you must be of above average intelligence, more importantly, you must have time not consumed by meeting your daily essential needs.
Example 2: you must have some product to sell, one that you can make and sell in volume, there are other sites that allow handicrafts, but its hard to make a living off of handicrafts, and its a big leap to go from individual production to serial production in a factory without capital.
Example 3: you must have talent for doing something worth watching, otherwise it doesn't make money.
Example 4: same as example 3, though, perversely, if you're really really bad, you can actually make money, but being that level of awful is a talent unto itself, and most people are not willing to subject themselves to that level of humiliation.
We have massive issues with access to the legal system by the poor, we've extended the cult of personal responsibility to the extent we now just blame the poor for being poor. We also treat debt like a sacred obligation, if your wealthy its easy to discharge debts thru bankruptcy, not so much if you're poor.
I wrote a huge paper about this with a friend of mine last summer. Please take the time to read it, and I think you'll understand more about why I feel so passionately about this.
https://docs.google.com/document/d/1Bfu3pw1pid_2HcDYeAlSyj21...