Now this is why there is discrimination among North and South. South languages are tough hence its not possible for every north to learn it. Now South States are restricting outsiders to come to Chennai because whenever someone will visit there he won't be able to communicate with them.
This will definitely irk North or any other citizens. Now i am sure someone from Maharastra will also start advocating to make Marathi compulsory. Gujarati will also do that. So, this will create a discrimination only among the integrity of India. If JJ is keen on making everyone learn Tamil since childhood then let her also assure that no one will come out of her state and will remain there interacting in Tamil forever.