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.
I think this gets a little muddied in The Discourse, because tons of pro-market anti-monopolist and anti-cartel[1] policies (like, you know, any preference for more trust-busting than the post-late-'70s neutered version) get painted as socialism in, especially, the US, simply because it's regulation and since the rise of Chicago-school jurisprudence and legislative influence, the fall of anti-capture and money-influence-mitigating regulation of media over several decades, and generally the ascendance of the Reagan-associated neoliberal outlook across all of mainstream American economic politics until very recently, regulation is the enemy of capitalism in many folks' minds, even when it's (god this is frustrating) laser-focused on making markets freer in the sense of their function, not the sense of "less-regulated".
The result is that people who simply think "barely-regulated markets" aren't fix-everything magic fairy dust that can't possibly be improved by a couple more laws and enforcement mechanisms, or even in a some cases by flat out replacement by a government program, find themselves rhetorically connected to nationalize-much-of-the-means-of-production Marxism-curious socialists (besides not being so removed from Nordic-style democratic-socialists to begin with)
[1] frankly, I find it convenient in certain company to shorthand "shitty tending-toward-captured markets, sacrificing efficiency and human decency for the comfort of a few" as "capitalism" given the actual outcomes and evident tendencies of systems the leaders of which emphasize and tout how capitalist they are, and the frequent expressed and revealed preferences of folks who like to promote themselves as particularly capitalistic, for the same reason it's kinda fair to regard communism as authoritarian and anti-democratic in practice, but I'll gladly entertain other usage for the sake of conversation.
The identification of "freedom of market participants to do whatever they want" as being the "free" in "free markets" is exactly the problem here, in my view—and I'd go further and claim that confusing the two things has been a deliberate sophistic practice (among others, chief among them being "please don't notice I snuck in a couple sketchy axioms and 'as we all know's at the beginning, so that you accept the hundred pages of 'reasoning' based on them that follow") promoted by figures in some allegedly-intellectual circles, to make themselves useful to those who find that kind of thing beneficial, and so to personally gain from being professional BS peddlers.
(I'm not correcting you, here, just adding on—I'd guess we basically agree on at least the first, and most directly relevant to your post, sentence of the above)