What is the purpose of having indices like Nifty50 PR 2x when they are not tradable, even after being launched so long ago? As far as I can tell, no mutual funds use them as benchmarks either. So what is their actual use?
There are also other similar indices, such as:
What purpose do these indices serve in Indian markets?
These are probably for FIIs.
Do they use as benchmark or something else as they are not tradable like the US markets
yes actual use seems only for analytical purposes/benchmarks. maybe a few workflows might be integrating it so they did not remove it
SEBI should allow these products including options on ETFs with a warning it’s for active traders. 
Yes, they should—but they won’t. They’ve drifted away from being a regulator and now act more like a capital protection authority, stepping in to “save” people they assume don’t really understand the markets
While I don’t agree with measures like restricting 0 DTEs and weeklies, it’s understandable given their study revealed 93% of retail traders losing money that they had to be seen doing something. 
In every industry, the chances of success are quite low. Even in startups, around 90% fail—but that doesn’t mean the government should stop promoting them or restrict them in any way.
Measures like these by SEBI will only prevent our markets from maturing and from attracting global capital.