Mahavir - I think that RG Should not be made compulsory for PG students because world over PG Students are not well versed with research and lack the necessary training and skills to carry out research, with some exceptions to the trend.
The fact is that only a minority of research scholars, colledge teachers and university teachers have their account on Research Gate, Google Scholar etc. In future, there is possibility that with more research facilities and guidance PG students may be involved in carrying out research.