> Determining whether there is an actual labor shortage is pretty difficult.

The only hard part is nailing down what people mean by “labor shortage”; resolving whether one exists under either the normal economic definition or the one people are actually using is pretty easy, but since the whole point of using the term is to mask that the actual complaint is about wages being too high, its really difficult to get people to admit what they are talking about.

Yep, almost always in rich world "labor shortage" = I can't / don't want to pay a livable wage.

Over here in Europe my country has a sky high unemployment, yet picking tomatoes is mostly done by immigrants from Southeast Asia. The pay for that hard work is so bad that most natives won't bother, but it's okay if your plan is to save for a few years with absolute minimum budget, and then return to somewhere with much lower cost of living. I guess it's just the same with Latin American migrants in America.

Japan has historically been pretty anti-immigration, so they might prefer robots over this arrangement.