The introduction of modern education, the improvement of women's lives, the improvement of infrastructure as a result of the construction of railways, hospitals, and schools, modern governance systems, as well as the introduction of industrialization are just a few of the positive impacts of imperialism/ colonization. Look no further than India. South Africa is another great example and everything was given to the present government on a silver platter but those now in control screwed it all up. Once a thriving country, south africa is extremely dangerous and corrupt. Ethiopia was one area of africa not affected by imperialism ( unfortunately) and it continues to be a very primitive country and one of the poorest in the world. The economic benefits of imperialism are palpable. India clearly took the ball and ran with it. They have a way to go but its looking good. Africa is another story unfortunately.
Imperialism/colonization is a little more nuanced than that. The growth in wealth in the U.S. traces back to Cyrus J McCormick. His genius was at inventing and designing the first mechanical crop reaper (1845?). But his genius didn't stop there. He also knew his reaper empire would be far flung. How can one man manage that? So he envisioned the concept of Dealerships who would represent the company, sell machines and parts. In exchange the dealers would participate in McCormick's profits. "Dealer Markup" was born. This did not go unnoticed to other industrialists. As soon as Henry Ford got started, Dealerships were crucial. To this day, there are Ford Dealerships that remember the day Henry Ford stopped by. For this model to work in other countries is easier said than done. But good luck to all of them.
You're implying that imperialism and colonization were the reason some areas prospered without any facts or data. you need to look at the land itself. the geography. most countries: USA, Australia, African continent, S. America, ... have high majority of populations at the coasts. Africa is a mound with a small coastline; it's geographically disadvantaged.
Japan was never colonized nor under imperial power, the first outsiders arrived and reported how amazed they were about the developed society and organization. There are examples that show how imperialism and colonialization did little to nothing (many african countries) to improvements of the average livelihood and standard of living. Others prospered. And there are countless nations that incredibly prospered without the slightest hint at colonialization and imperialism. Hence a country's success at delivering opportunities and a good living standard have very little to do with imperialism or colonialization. It has much more to do with choices and attitudes toward economic wellbeing that certain groups utilize or ignore. Most importantly, the biggest guarantor of success is whether the individuals of a certain group display a sense of responsibility and duty towards contributing to the common good.
Not sure who the "you" is in your post, me or the OP. If you are addressing that to me, the nascent U.S. had the distinct advantage of being populated with Western Europeans who were extremely eager to improve their lot in life. Couple that with a Code of law that would protect property owners (both real and intellectual) and that became a recipe for success. As said good luck to other cultures and countries.
I guess ET finally has its own Karen. Man, doesn't this sound downright bigoted, or is it just me? Those colonizers weren't exactly benefactors with kind intentions. They came and exploited the colonized nations mercilessly. They didn't give them railways, hospitals and schools out of good intentions. This place is filled with too many naive Karens.