Chromecast and Firestick work with literally all the streaming services that we have available in India

But is that the only alternative? Why is it not possible to do it with the plain old hardware like raspberry pi?

Maybe because Raspberry pi is not a mass market hardware. Also how many in that small population are using it to watch streaming videos?

Raspberry pi is for hardware enthusiasts and not for end consumers. Pi 3b costs 3000Rs. A Nokia 1 phone(android) costs 4000Rs. What are people gonna buy in these two?

Well, people can also have old laptop or desktop pc which is same as having a raspberry pi.

Yeah but hotstar targets mobile phones and latest web browsers. If you can run any latest browser in your Pi then you should be fine

That still involves more friction than just casting to a Chromecast or Fire stick