There's a difference between being ready to seize a realilistic opportunity if it comes along and being told that there will be opportunities if only they work hard. I'm guessing that opportunity that came along just happened to better than the opportunity to sell weed on the corner, right? I'm guessing there are others who see an opportunity to work a low paying job as being less of an opportunity than selling weed.
I don't think it is nearly as bleak and binary as people make it out to be. If you look at the actual data, there is still a lot of opportunity for upward mobility. 60% of people who grow up in the bottom economic quintile improve their situation. [1] When thinking about the 40% that dont, there are a few notable facts:
20% of children in the bottom quintile dont graduate highschool.[2]
8% of men born into the bottom quintile are currently incarcerated.[3]
The traditional advice to children for how to be in the 60% that escape poverty is still true. Stay in highschool, stay away from drugs and crime, and go to college if possible. If poor children can do this, their chances of improving are actually quite good and not at all hopeless.
Of course, better opportunities may come without working hard. But in my case the opportunity was only realistic as I spent years preparing for it. If I'd spent those years doing and selling drugs the opportunity would've came but it would have not been realistic for me to seize it.