Interesting letter Imolderu. And that's just the way it is. Much like the article in this thread. The rules are not equal and never have been.
As to leaving home and breaking the cycle...I think birth order has something to do with your place in life, too. First borners leave home and strike out on their own more often than the other nestlings?
I think that's often true. The more dysfunctional the family, the quicker the firstborn must grow up. DH and I are both first born. I come from your "typical" middle class family (some dysfunction, some good -- how much you let it influence who you become may depend mostly on your in-born personality). My husband on the other hand grew up extremely poor. We just got back from a trip to his mother, trying to help her out -- and that experience is why this thread caught my eye. She's one to talk about how rough her life is, but most of it is her own making. DH grew up with this hyper-religious, angry, hoarding mother, and yet NEVER complains about his childhood. Mostly, he's pretty flat about his past (neither nostalgic nor angry). It's one of the things I most admire about him. I had more resentment about things from my childhood than he, and I've learned to better appreciate what I had.
As to the question of breaking free. DH was born at the end of 1949, but grew up without a father and even without indoor plumbing. However, he was born very intelligent, and perhaps because he was the first born or because he was kind of a nerdy kid, he studied hard. He was his high school valedictorian, and attended college on a full scholarship. His mom still had a copy of his valedictory speech, and this shows just how much he grew because of going away to college (he went out of state). So, I agree, had he not gotten away from home, he might not have done as well. However, he is also white, and was poor rural (not poor inner city). I think inner city can be harder to break out of, and actual abuse can be devastating. He didn't have those hurdles.
Another thing, though, is that people tend to determine how well they are doing by comparing themselves to others. When you come from this type of background, everything is so successful in comparison, that a person might not push themselves as hard. While we are certainly what most folks would consider successful, would he have accomplished more had he had that expectation and example all along? Probably. I don't know that he'd be happier -- we're content. But still, it's likely someone with his intelligence would have accumulated even more, pretty effortlessly, given different expectations from the start.
However, his mom must have done some things right, as both him and his brother did fine, and her grandkids are also in good shape (none wealthy, but solidly middle class). I think his brother married the right woman, and wasn't bothered that she earned more than him. This may be due to the rural family values, which provide a framework even when poorly applied.
One final thought (sorry this is so long). DH and I understand the the experience of people in poverty. Some folks do make poor decisions or get stuck, but it doesn't make them any less human. I've seen as much bad behavior from non-poor, but they often just have a better safety net. We don't sit in judgement and expect perfection from poor people, when we ourselves make mistakes, and much of what we have is luck or having learned how to spot and take advantage of an opportunity. What we find unfortunate, is that some of the poorest people (at least rural) are the strongest supporters of politicians whose platforms are harmful to these same folks. My MIL recently had her SNAP benefits decreased. She's upset about that, but is uber-conservative. She doesn't think she should have to pay anything to the government for programs to help "those people" (which, she doesn't), but thinks of herself as a good person who just fell on hard times and should get help from the government. She sees herself and her benefits as different from the no-name poor masses. She's sort of indoctrinated into these conservative beliefs, without getting how it applies to her situation. I think this is a real issue among a lot of rural poor.