The reaction to unions over the last 50 years is what doesn't make sense to me. In oligopolies where businesses work in collusion to to remove their respective competition, and then price fix their product market, the public's reaction is: "oh my, how terrible".
Yet using the same logic, the labor market unionizes, acts in collusion to work together with their labor competitors, price fix a labor purchase point in the labor market, and the public's reaction is: "wow, what a great thing".
Its the exact same practice in different markets yet somehow the public acceptance of each is completely different. Labor markets were turned into monopolies within our borders until free trade agreements opened the labor markets back up to international competitors (which also has its own problems without tariffs to equalize the value of the respective economies).
I believe government regulation of the labor market is the better solution than monopolization of the labor market.