So far it is only mandatory for companies to do so. For companies bringing this control is pretty easy you just add this point in the Annual Return that all the companies are required to furnish and tadaa , you will get details of all the crypto holdings of these companies, I won't be surprised if in future this comes in the Income Tax Return as well, and if it comes in that then obviously every person will have to submit their crypto holdings and government on annual basis will have details of all the crypto holdings that people are holding, but to be honest, for individuals atleast it's pretty easy to hide any such holdings from government, for Companies it's impossible because you eventually have to give detail of each and every penny spent.