RBI is not going to build end products or offer financial services, it is exploring moving only the book keeping aspect to itself. So I don't think that example is correct.But why is this desirable in the first place? The job of the Reserve Bank is managing currency and monetary policy. This is like asking FSSAI to make biscuits and potato chips.
If the cost of maintaining a distributed ledger via RBI is lesser than hiring people to do book keeping, audit and repair damage from frauds. Why not?
Cost of borrowing in India is very high, anything which allows for more liquidity and transparency at a lower cost should be welcome.
We just need to be ensure adequate safeguards to prevent abuse and protect privacy are in place.