Blocking access to a portion of the internet is a way to offer up that portion packaged in a nice fat subscription later on by the company that blocked it in the first place. It's basic market tactics.I'm not sure what's profitable over doing this..
Wait for a while. You'll see Jio offering their own "secure" "Desi" "made in India for the world" VPN service. It's a matter of time before large popular applications are banned and replaced with "sanskaari" alternatives. Koo is just the start.