Let me start by saying that ‘3 idiots’ has a 100% rating on Rotten Tomatoes. Yes, there are only 6 reviews but all 6 are postive reviews from American film critics. Obviously the general American audience would not have as much of a connect with the film as we, as Indians, live in the society and have had the upbrining that the characters in the movie have had. Since it is a film that drives home an important social message that is exclusive to the *Indian* audience, it will certainly not have the same effect on an American viewer.
But, that does not mean that it does not make sense to them. A movie may seem great to different people in different ways. For an American audience, this is an insight into the mindset of the Indian society regarding education and proffesion. Not all the jokes can be appreciated as well as the Indian audience do but even when a normal Indian viewer sees a Hollywood film some cultural references do not seem as entertaing as they would to an American. But this does not mean that we do not “enjoy” Hollywood films. There are also parts of the film that are just fun and witty and when viewed by anyone across the world can be enjoyed (obviously with subtitles).

Anyway hope i could help. Everything that I’m saying is from experince; when i watched this film i was living abroad and had been so since my childhood but having Indian parents and relatives I would visit every year I could still understand the mindset.