You certainly have a point there. The difficulty is that touching a state government that doesn't want to listen to you has become infinitely more difficult after a succession of judicial challenges. Now no government at the Centre wants to fall foul of the courts, risking some action against the state governments.
In the special case of Kashmir, the Kashmiris themselves have firmly resisted any attempts at change. For instance, the Ranbir Code prevented alienation of property to anyone not a permanent resident of the state. Ironically, this was intended to prevent any alienation of the landed estates of the Kashmiri Pandits, who got liberal grants, to outsiders from the Punjab or further. Now, this has been re-validated by the State Assembly, in the teeth of a storm of protest from civil society in India, and the renewed wording prevents women from inheriting if they marry a person not a permanent resident of the state.
With the Ranbir Code and the restrictions of Art. 370, there is little that can be done to Indianise. And that is a pity.