It also ignores the extreme improvement in the US social safety net since the late 1960s, which is generally ignored in such discussions. That has improved the lives of the bottom 1/3 by a lot, which is not captured at all in the wage growth figures. As one example, it has led to a very large improvement in childhood poverty rates (about a 50% reduction in childhood poverty since the early 1990s):

https://i.imgur.com/OrMwlkT.png

You can also see that wage growth by the bottom half has soared (up four fold since mid 2013), and is now well outpacing wage growth by the top half:

https://i.imgur.com/Mi6mgme.png