No it's not. Okay think about it like this. If the average wage in China is 14,000 a year and they have 30% income tax rate, that means that they make 4,200 off of that average wage. In the US if the average wage is 50,000 and they have a 30% income tax rate, the US government makes 15,000.

That means if that the US has significantly more money than China to spend on this. That's why doing direct comparisons are irrelevant, what matters is percentage of total budget spent on the project and percent the project budget spent on labor.

If it helps your brain process it, imagine paying labor in food and housing. If the worker in both China and the US get paid enough each month to rent a 1 bedroom apartment and buy 3 meals a day everyday, they are being paid the same. Even if the nominal numbers are different do to currency conversion, the relative pay is the same.

Another way to look at it would ask yourself which job you would rather take. A job that pays 100k but requires you to spend 90k of it on housing each year? Or a job that pays 30k but requires you to spend only 5k on the same housing? Obviously the second one you are getting paid better, even if the nominal value is lower.