Your critisism of Hindi is unwarranted. Indian Students are learning French and German as second language just like Hindi. Nobody is forcing the Tamils to learn Hindi. I know many Tamil friends in Delhi and Mumbai speaking good Hindi. Those who live and work over there need Hindi as communication language. What is wrong if the Tamil students of Tamilnadu who plan to have a career in North India learn Hindi?
Do you think by learning Hindi you loose your culture? no way instead you are loosing your culture by learing English, Frech and German.