Capital is more mobile than labor, so it has a built-in advantage in being able to relocate to where labor is less expensive.
In addition, there are other trends that are making the US economy less favorable to labor. One of them is the increasing concentration of business so that many sectors are now dominated by oligopolies or even monopolies, due in part to less aggressive anti-trust or anti-monopoly regulation. For example, how many health insurance companies can you choose from at your non-government employer or ACA exchange, and how many medical groups are there in your area to choose your physicians from? Not only does this result in fewer choices and higher prices for consumers, it also results in fewer choices and lower pay for job seekers selling their labor to the smaller number of possible employers.
You may also want to see this post #10 by @blossom at The grim state of Pennsylvania's state system: news article today - #10 by Creekland where the changing situation of journalism jobs is likely related to the increasing concentration in media businesses.