I think the one bit you've not covered here is the children. While the parents likely will live a life of difficulty and work, their children become part of the American education pipeline that makes it quite likely they will be, if nothing else, integrated into society in a manner that will make their taking the next upward class step much easier. The parents are taking the hit to their livelihoods and careers to enable the next generation to be more successful. It's not a guarantee, but probably more upward mobility here.