There are millions of students in India, China and other developing countries doing everything they can to take the highest paying jobs available. In the U.S. if you don't work for the government (and that isn't increasing), there will be a steady transition (20-30 years) towards the service and labor industries before labor drops off completely.
Local small businesses like plumbers, knife sharpeners and gardeners are the new middle class. They own small businesses that are difficult enough and require expertise or complex machines to reduce competition but not so much that they can't compete with the conglomerate. Electricians, Home Inspection and Tutoring are businesses where certification is an expected but the other barriers to entry are low. Expect these businesses to grow as people look for alternatives to the corporate ladder. This trend of local labor intensive entrepreneurship will grow for the next 15-20 years until robotics and battery technology begin to compete.
Medical Doctors commonly had their own private practice, but with the past 40 years of regulation, the private practice is going away. Dentists, chiropractors, and attorneys are, so far, less affected by these changes. As a business owner they needed to know so much more than they do now, they needed broader perspectives and an ability to manage incredible risk, and they are making proportionately less than ever.
Professions have changed from being traditionally business owners to being equivalent to tradesmen. 100 years ago, engineering firms were often 1 person companies, now these businesses are being outsourced overseas. Accountants, financial consultants, software developers and every other profession that doesn't require hands-on participation will continue to see a shifting of the workforce. This shift may even expand to those physical professions as robotics extend our digital world. The small businesses who cut your grass, serve your food and wash your car are becoming more common.
We have more pressure to earn advanced degrees, and less real world incentive, as education in previously "third world" countries skyrocket and wages race to bring balance. The high earners in the U.S. are finding themselves not middle class, but top of the lower class. Earning $100k was once a benchmark for success, now it means having granite countertops and owning a newer vehicle.
The U.S. workforce will change in several ways.
There will be massive amounts of highly qualified people who won't be employable. They may still be productive and valued by society but they will no longer have Jobs or be seen as contributors to the economy. Some real innovation and creativity will certainly come from this group.
There will be a group of people who continue to push forward in the traditional work environment, competing with the best the rest of the world for a shrinking number of jobs for the highly educated as machines and humans compete.
Fewer and fewer will consider themselves truly poor and the difference between professionals like software developers, engineers, entrepreneurs and people not working in a traditional sense will be less and less noticeable.
Some might say that there could be a massive revolt, but I find that unlikely as the cost of goods, services, transportation and energy drop. It is unlikely that people will feel repressed, overburdened or unable to express themselves. I want to state, that this isn't communism. This is a natural progression of the mix of capitalism and socialism that we are currently in. Goods simply cost less, to the point where in 40 years, Maslow's hierarchy of needs will be an after thought. Life will cost nothing to live, and work will be what you want it to be. Getting to that point could be interesting, quite scary for most and painful for many.