Have they? The state of labour laws in the countries which produce cheap goods sold to Western countries seem generally poor, especially given the timeframe for which this has been happening. It's also suspect how work is treated merely as a matter of wage and benefits rather than a question of the nature of wage labour itself.
Unequivocally yes! Understanding this ironclad fact is one of the most important things to understand about changes in the world economy over the last 50 years.
China has gone from a country full of subsistence farmers to a country of middle class wage earners.
That wasn't really the question being asked - the question concerned more, whether, for instance, people feel happy working for wages, under working conditions that seem set fifty years in the past to any Western observer, and what the quality of life is like in conjunction with the regimes which typically administer these policies. The argument, to me, seems rather similar to the argument the English bourgeoisie made during the industrial revolution - and it rings even less true when you realize that this new wage earning class is largely not composed of the same group of people who were subsistence farming.
From the perspective of a critic of wage labour (and class society), one form of domination in substinence farming has been replaced by arguably a quantitatively better but much more cunning and egregious one, which disguises its aims through the mantra of freedom to buy and sell - and you won't find many people who would give up that freedom now. That doesn't mean the freedom is desirable, it just means it's better than what came before.
I don't have a hard time saying that people's live are a lot better when they make enough money to afford things like reliable shelter, a better diet, access to medical care (Chinese lifespans have nearly 2Xed in 70 years) & modern transportation.
In addition, while working in a factory making iPhones might not be the best of jobs, it's a hell of a lot better breaking one's back on the rice patties every day.
My point is that the comparison is disingenuous, you're comparing the thoughts and feelings of people situated in one group of time to the ones today, and it doesn't address the fact that wage labour brings its own, more transparent problems - alienation, risk, and domination among them.
When you compare living conditions and material benefits, of course the world is better, but that comes at the moral cost frequently expressed as "sweatshops are necessary because the country becomes richer and you get better living conditions". I don't know how this is justified, this kind of trade-off is not justified by any major ethical system, including most serious forms of utilitarianism.
Consider the case of a Chinese peasant farmer who has has land confiscated by the regime, so now he gets to make iPhones to earn a wage so he can spend it on buying food and shelter and medical care. The conditional freedom of needing to sell one's product (whether that is a material thing the peasant makes, or the labour power the iPhone factory worker produces) hasn't been eliminated, it's just changed form.
You claim to be able to reduce these factors to a comparison in which you can say one is better than the other, and I'm not convinced the reduction is sound. Most people, even our iPhone factory worker, would think that there is (and there should be) more to life than the wage and its spending.
Chinese people used to starve to death all the time because they couldn't afford to buy food. Now that happens much less often because China has gotten much richer through international trade.
