Would they need BTC? With 1.3 billion potential users wouldn't that be enough?
It doesn't matter if they create their own coin, in the end it will be centralized and the one who want a decentralized one will choose bitcoin. It's not the first time some country want to create their own crypto currency, they are free to do that but the only user will be that country civilians and not the people from other country because they will choose something better.