yes, but just calling it Indian ocean is not the same as Hindu ocean.
There is a similar distinction in Russian language.
When we reffer to something we can use 2 words. Rossiyskiy or Russkiy. Rossiyskiy, meaning pertaining to modern Russian Federation multi-ethnic state, and Russkiy meaning ethnically Russian, excluding everyone who is not Russian in the most nationalist way. Russian Federation under Putin avoids using the word Russkiy in many ways, and preffers to use Rossiyskiy to underline ethnic unity of modern Russian federation and to avoid pandering to extreme nationalists.
But in India they WANT to pander to extreme nationalists. So when they say Hindu they are in a way excluding non-hindu Indians and everyone else. These obscure language games are really important and should not be overlooked.