I think u r missing the point here. The Nano car has been built not to compete with the world-class cars. It is more of a technological and management innovation which caters to the need of the common, middle class Indian citizens. If the matter is of comparison (like a car to a lawn mower), I'm sure there are various Indian technology and innovation (some informed friends may pls help me out here) which is not only world class, but of even superior quality than many developed countries. (I guess the Delhi Metro is one such example, or the Konkan Railways, or the Reliance Industries and their refinieries).
As T.P.Bhatt (above) has correctly mentioned, these people have to react. And what better way than to criticise something that you cannot achieve urself !!
It's these moments when Indians world over find another reason to feel proud and can hold their head high.