First you need to understand that true IPTV is unaffordable even in developed countries like USA and UK. True IPTV does not even exist in these countries.
What is currently being provided is virtual IPTV (vIPTV). Virtual IPTV can be a boon for several channels in India because of the a-la-carte policy of MIB. Once again all unnecessary channels can be provided to the user with no option for the user not to take these channels.
Also, separate STBs for live TV and OTT is desired by many who have only internet connection on TV.
The live TV STB can have a remote designed to smoothly operate live TV whereas the OTT STB can have a remote designed for operation of OTT apps.