There are some well known contributing factors:
No belief is more firmly held in Republican dogma than that the Reagan “Revolution” turned the US economy around from perpetual stagnation to strong growth, with consequent benefits for…
aneconomicsense.org
I'm not sure what point you're trying to make since you just linked a bunch of images. The graphs seem to suggest that the reason wages didn't keep up with productivity is union membership. That really doesn't make sense since even when wages were tracking productivity increases most workers weren't in a union and if you wanted to show union membership actually being beneficial you could just do that directly by comparing wage growth between union and non-union members. Or you'd just look at other countries where union membership is considerably higher.
Of course if you do that the argument largely falls apart. The wage growth in other western democracies is similar over the same time period despite almost all of them having a much larger percentage of workers being union members and being disconnected from U.S. political and economic policies. Denmark has more workers in unions than not (about 66% from recent figures), but have seen
the same low rates in nominal wage increase over roughly the same period as the U.S. Other European countries I looked at (specifically Germany and Sweden) had similar numbers for wage growth in that period.
Wages fall off right as China and other asian countries started to open up their markets. The Open Door policy was started in '78, which is when China opened the country to foreign investment and created a massive supply of cheap labor. That's probably not the only explanation. Computers and robotics also saw a lot of advancement and adoption over that timeframe as well and completely changed many industries. Women also started to enter the workforce in larger and larger numbers which substantially increased the labor supply.
Our labor is more productive than at any point in history, but it's almost entirely a result of computers, robots, and other industrialization. Of course the flip side of this is that thing things we produce are now less expensive, which is why even if wages were completely flat (excluding inflation) people would still have more purchasing power than previously.