The problem in this country isn't unemployment so much as underemployment.
I don't believe there's an underemployment problem either.
Usually when people talk about underemplyment, they're talking about two things: (1) the decline in industrial manufacturing, and (2) the quality of starting positions for college grads.
As to the former, the country has simply matured. The days are over when millions of high-paying union jobs allowed workers with no more than a high-school education to purchase homes and save for a comfortable retirement. It's been proven untenable in industry after industry (steel, auto, airlines, coal). No one, not even the government, can hold back the flow of time.
As to the the latter, the problem isn't the jobs, its the job seekers. Millennials are largely a spoiled, entitled group. They're not good workers, they're not committed employees, and they're delusional about economic realities. They want the lifestyle of their parents without doing the work that their parents did to get it.
And as to the "good" Millennials, their problem is their student debt. The jobs are there and they pay exactly what a college grad deserves to get. But when you factor in the blooming student debt levels, real wages and standards of living are falling for recent college grads.
But how do we fix that? Raise wages? Why? Today's college grad is no more valuable in the labor market than the last generation's college grad (arguably less so, considering the decline in the quality of college education). If Millennial workers aren't worth more, why would we pay them more? Again, the problem isn't the jobs -- it's the job seekers.
The solution, if any, needs to come on the student debt side. I won't pretend to have the answers for this situation, but I do know its not a problem that can or should be "fixed" by businesses.