I was in same boat for fourteen years. I left US about four years ago and absolutely no regret. Yes, it is dirty, corrupted and occasionally you get frustrated but I am much happier here. Personally, what I have noticed with immigrants in USA was, so call American dream( card, 9-5 job, house): if you got all three within eight years then it's the country for you if not get the he'll out from there.
The most people who left for school do have some kind of backup property in Nepal and those who went on DV(most of them) also do have some property in Nepal. Property is king in Nepal. You can get loan very easily with property back up. Registration of business is bit hassle and time consuming but once you are done your US experience will come handy. Most of the smart people have left the country for US, Europe, Australia and hard working people have left for middle east and Malaysia so you can be Lato ko Desh Ma Gado Tanneri.
I am amazed by most of the people who comes to Nepal for vacation, complain that it is getting so expensive and going out in a restaurant with a friends might be even more costlier than US. And second amazement is how can they afford it, well that's the answer right there. Some one is making or getting money, some how😀. Car price in Nepal is four time more expensive than India, US. With this poor economy and poor country, there should almost no car in the streets of Nepal but look at thetraffic jam and how may person you know own a car in Nepal?
Yes, the grass is also greener this of the world too.