I don't debate your four examples. They're nice, but do nothing to refute what I stated. I didn't claim it was impossible, or even that difficult to "rise up" (as if that should be our goal) in America. I did it myself, in fact, and I'm comfortable stating that because it doesn't negate what I said. My point instead is that spaces are very limited, and that's part of what capitalism constructs for the world. For every person that does move from the lower or working class to the upper middle or upper class, there are probably 100 or 1000 that don't, and it's not all for lack of trying. And I wasn't attempting to make the claim that only .000000001% (or some such arbitrarily small number) "make it."
There's this issue, and also the fact that Americans, and especially, foreigners that move here, are supposed to buy into the idea of "American Dream" in that not only is upward social mobility achievable for everyone, which is a flat-out lie, but - more problematically, to me - that they're supposed to WANT it. I can't think of a more misguided goal than spending your life enriching yourself.