One fairly high-profile (yet topical) example of this is the top flight of German Football. East German teams rarely even make the German Bundesliga[0], and my understanding is that there’s currently only one Eastern German team in the 20-team league.
0: https://www.theguardian.com/news/datablog/2014/oct/17/west-g...
Building up North Korea isn't hard, living in North Korea is hard.
The reason it's important to me to say so is that at some point, some actual people with actual (limited) resources, will have to devise a plan to make it all better, and then actually do the plan. That is a huge challenge that involves trade offs and hard decisions. And if you start with magical thinking, instead of extremely realistic reasoning, you're going to end up hurting a lot of people.