Virusno1, I think you are making a subtle mistake. Which firm did you apply for? I am sure it is a not-so-important position in some not-so-great firm.  Most of the reputed firms, which aim to develop cutting edge technology,  aim to hire people who has potential to contribute to those goals, and they do look at the graduates of top schools. These are the firms that go to the top schools, hire top graduates and try to make their mark in the market.

While it is common to find students from the schools which are not very highly ranked in these firms, an overwhelming number of the students hired recently are from top schools. They look at the graduates of lower ranked schools only if they can't attract talents from top school, or only if they believe they won't be able to retain these talents once they are hired.

Not many Nepali students have made it into top graduate schools, top firms, and so not many Nepali graduates are millionaires in making. This has in turn fed our own illusory perception about whether top schools matter. They matter, because they signal something to top notch employers. They matter because you are likely to rub shoulders with the top class professors, top class classmates, and you are likely to attend seminars of top scientists of our era. You are also likely to meet the hiring officers from top research firms, top technology firms, or top financial firms there. You get an experience that is rarely available at the lower ranked schools. If you can make it to top schools, go there. Aim high, and encourage other Nepali to go there too.

If you can't make it to top schools, never discourage others from going there. As for yourself, wherever you land, make sure you work like a charged bull when you are in the school. In USA, you have no other qualification but your own GPA and CV. nepalko source-force le yahaa kaam gardaina. So, keep working hard.