The remnants of colonialism continue to produce winners and losers economically, with the winners stuck in local maxima where they extract value from the people, but the people themselves see only marginal benefit, and development is stuck at a snail's pace.
As with seemingly everything in life, the incentives for the different players really don't line up. Consumers lose, producers lose, and only a select few middlemen win anything at all.
The reason New York City is the biggest city in the US is because when the Erie Canal was built, the agricultural riches of the Midwest had a route to world markets. Where you have a major seaport, you also need major banks and major insurance companies to smooth out the financial needs of traders and shippers, providing the funds right away back to the farmers, instead of them waiting till the voyages were complete. (without the Erie Canal, New Orleans would have become the largest city in the US)
Yes, there is a lot of money in trading, banking, etc. At every step of the transaction pyramid, a %age is added to the price, and the %age fees charged on that go up accordingly. But that measures the true value of the product at each stage; if you have a cheaper way of getting the same product to the same stage cheaper, the (supposed) riches will be yours.
The socialist instinct ("anybody getting rich must be cheating") unfortunately obscures the real problem ("monopolists and cartels controlling supply and setting prices are the true enemies of the people") which hinders solving it; by putting capitalism in your gunsights, you make enemies out of natural allies.
It is not pleasant to think about it in these terms; but it does seem like some of the greatest improvements in general human welfare have their roots in relatively ungenerous undertakings by methodical, reasonable, self-interested actors. The Romans roads and the Pax Romana, and the profound legacy of Roman law, were not the result of a benevolent desire to help everyone in the world and save them from evil.
There's something unsettling about the might makes right amd post-hoc justifications dor colonialism. Especially considering the colonialists did not have those "noble" goals in mind. No one lauds Google the way they laud the British empire, yet the same exploitation vs. public benefit arguments apply.
To dismiss the Romans, the colonials, &c, as of no benefit, however, is to deny reality. The Roman roads were genuinely of value to peoples besides the Romans. Perhaps the Chinese, to, will create institutions and a scope of activity that is of value to peoples outside of China. Probably not in Asia...
At no point did I dismiss the knowledge-transfer as being of no benefit. The point I was making is that it is very easy to be on a high horse and say "It was worth it" when you were not on the sharp end of the stick. By reframing the set-up with China as the imperial power, I hope to show the readers that the cost of "upliftment" might be something the unwilling subjects may consider culturally valuable (like democracy)[1]. Such one-dimensional analysis is intellectually lazy.
1. Imperialism has been dissected many times over the centuries, in fiction and otherwise, but it bears repeating.