[blackbear_]

It definitely works in the short term, but what matters is the long term effects: how will people and businesses adapt, and will that lead to a better society?

Case in point: At least as far back as the 17th century, many people believed that idle children were a source of crime and poverty. To combat such idleness, apprenticeships were common for children of working-class families. Child labor, rather than being viewed as exploitive, was often considered an act of charity (https://www.bls.gov/opub/mlr/2015/article/labor-law-highligh...).

In the early 1900s, one could have argued in a similar way as yours and argue that enforcing a minimum age for workers would reduce the labor supply, leading to increased labor cost, leading to reduced profits for companies, leading to higher prices for consumers, leading to less demand for products, leading to less innovation, reduced standards of living, and so on and so forth.

Maybe that did indeed happen in the first years, but the long term effects were inarguably positive for everybody.