No, a "ceiling on American wages" theory would only make sense if globalization was removing jobs from the USA, in which case you would not have a labor shortage. It would be reasonable to say "Foreign competition has stolen jobs from Americans, therefore the unemployment rate is high, therefore there is a ceiling on American wages via globalization."

But that can not be reconciled to "labor shortage".

A more fruitful line of research focuses on the growing power of monopoly, and the collapse of new business formation in the USA. Why don't companies with huge profits reinvest their profits? Why are most of the tech giants sitting on piles of cash? Monopoly could explain that, and would also explain a limit on wages that otherwise seems to defy market sense.