It's democracy and everybody is entitled to vote for their own benefit. When cars where invented, horse breeders should have voted for laws against cars.

Still, not sure if the typical worker can really be sure they are a net loser? They might have less money in the pocket, but if the TV they want costs only 10% of what it would cost without global trade, maybe they are still in the positive overall?

The problem is the world is always changing, and people and nations always have to try to keep up and adapt. Or maybe not, looking at the example of the Amish? What would happen if everybody would become Amish overnight?