The fact is that the common American has far more than anyone has in the past, and even the poor aren't fairing too badly, according to the US Census as reported here [1]
Your comments about vanishing upward mobility are very much debatable. There's plenty of reason to think that mobility hasn't changed. [2]
Perhaps even more surprising to some, while the middle class may indeed be shrinking, statistics show that this is happening by squeezing them up toward higher incomes [3] (this doesn't contradict #2, since it's a difference in counting income ranges versus n-tile demographics)
It's really not such an awful world out here. Some people just seem to want us to think so.
[1] http://dailysignal.com/2015/09/16/are-there-really-40-millio...
[2] http://www.nytimes.com/2014/01/23/business/upward-mobility-h...
[3] https://www.aei.org/publication/yes-the-middle-class-has-bee...
EDIT : in para #1 I said "Senate" when I meant "Census"