It's not laissez-faire that has increased living standards, it's the combination of the free market, union organizing, and resulting from that, regulation and the social safety net. Before that, there was still massive poverty. And many countries still experiencing poverty are lacking the latter half of that list.

Note that free market economics and laissez-faire economics are not the same thing. A free market requires a transparent market that's equally accessible to everyone, that's not dominated by cartels and monopolies, and that requires some regulation. Laissez-faire opposes that regulation and wants to give free reign to cartels and monopolies. Adam Smith explicitly warned against those, and pointed out the necessity of workers organizing to avoid being taken advantage of. And that, workers having negotiating power, that is what increased their living standards.

> We must also observe that opponents to laissez-faire liberalizations are by definition proponents of illiberal central planning.

This is bullshit. There's the entire free market economy in between those two extremes.