I didn't say it was going to be easy.
Generals are not supposed to give excuses IMHO (and I am not bad mouthing them).
My point is that Indian armed forces are created from the same people who go to other institutes too. They are equally responsible to create weapons they want with the quality and quantity they want. They can't say, we are just users/consumers.
Just as an example, we networking equipment to Reliance. They beat the sh!t out of our specs and make us modify existing software and make us build new hardware to suit what they want.
They do this with all vendors. They work with vendors.
One has to be organised and equipped for the intended job / mission. Armed Forces can very well do and they did it much before DRDO or DPSU came into existence.
If one goes a little bit into Indian history, it would not be difficult to find that all the jewels of India - Indian railways, Indian Irrigation system (Ganga Yamuna canal systems, Doab irrigation system, Western Punjab Irrigation system, Kauvery Irrigation system were conceived, created, built and run by Corps of Engineers of Indian Army. All major ports and modern shipping by Indian Navy. All your major and now being revived airports were created by Indian Air Force particularly during second World War. All logistic installation big roads, bridges, ferries, inland transportation systems were creation of Indian Armed Forces under the British.
All your big and beautiful cities like Chennai, Calcutta, New Delhi, Jalandhar, Ludhiana, Ferozepur, Fazilka, Lahore, Peshawar, quetta, Karachi, Bhopal, jhansi etc etc all are creations of British time Cantonments. Those were not cities but for Indian Armed Forces.
All your basic industries and industrialists like Tata, Birla, Llyods, shipyards, Marwari and Parasi developed to meets requirement of Indian Armed Forces. All modern agriculture came up in Western Punjab to support war efforts of the British in Aghanistan. Their contribution in Medical field has also been immense.
All your India knowledge, archeology, history, geography, culture, language, Forestry, mineralogy, Geology, agriculture was wide opened by British Army officers - the largest ever contribution by any group.
But let us not get into that.
They can still do it. But the question is, should they do it? What then will do their primary job. Independent India's defense requirements are vastly different from colonial India. Today defence technologies are somewhere else.
Transfer the entire ISRO, DRDO, DPSU resources, budget and Scientist to Armed Forces and then see things for yourselves. I apply your logic - we also come from you. We will do a good job. Though even today Indian Armed Forces have the largest pool of technically qualified manpower but to deal with equipments made by others.
But what you seem to be suggesting is to do something out of thin air.