For what it's worth,
@Kaptaan, the author mentions that the genetic analysis of the population is not complete. It is impressive evidence on one point of great interest to us: the possibility that the Indo-Aryan language was brought into south Asia by individuals, families, groups, perhaps even entire tribes of migrants from the region of the settlement of the Indo-Iranians. It has nothing to do with any sharp genetic divergence between the residents of present-day Pakistan and north India or west India; if you argue that present-day Pakistanis are genetically quite distant from south Indians and east Indians, you might be closer to the truth. A good point at which to start is to recall that there is no sharp gap that suddenly occurs in the genetic make-up of people living from 10 miles to the west of the Radcliffe Line to 10 miles to the east.
The point of the article is very simple; primitive OOI groupies like my friend
@Srinivas (and many, many more) are left disarmed by precise, concrete scientific evidence that blows a hole through their fond theories of the greater part of human civilisation having originated within India, and was carried out to the rest of the world by prototypical Brahmins and Kshatriyas: a 'theory' so feckless and without foundation that it silenced the academic community by its brazen refusal to be bound by the normally prevailing rules of producing evidence.
Having said that, it is equally important to understand what the article does not say. The existing masses at the time of these widely spread 'migrations' were not wiped not; genetically speaking, they remained the majority. There is other evidence to believe that they were dominated, their divinities were co-opted, their culture was attacked and supplanted (a process that continues to this day), and they were placed socially at a disadvantage that was cast in concrete by a period roughly two thousand to two thousand five hundred years from the time that the migrants seem to have come into the sub-continent (going by the genetic evidence).
The article does not denigrate the contributions made by those earlier migrants; indeed, it holds up for mention those who trickled in around 35,000 years ago, out of Africa, and we know that there were those who migrated slightly later and contributed enormously to the genetic inventory, especially in west India, including what is today Pakistan. The point that those in the west were closer, genetically (and presumably better, laughable though that construct may seem), to the very diverse peoples of the Near East and the Middle East is astonishing, to say the least; how close are the Anatolians, the Turks, the Arabs and the Iranians to each other? Forget about 'western' Indians, they are not even a homogeneous group by themselves.
An argument that Pakistanis are closer to other non-Indians than they are to Indians necessarily depends on clubbing together the east and the south with the north and the west, with which the population of present-day Pakistan has a great difference. It starts creaking at the joints the moment one examines the population of Pakistan in juxtaposition to their immediate neighbours to the east. Leaving aside the Baluch and the Pashtun, there is in fact little or no difference between the Punjabi and the Sindhi and their immediate neighbours to the east. When we remember that besides the migration of the Aryan speakers that this article addresses, there were other, possibly larger migrations, in the Scythian-Pahlavi ones, closely followed by the Kushan migration, and that these are closely linked to the people of Gujarat and Sindh on the one hand and to the Pashtun on the other. Are we to believe that migrations, of any time or of any kind, had an absolutely unique impact on the dwellers of the present-day Pakistan, and absolutely no impact on the Gujaratis and the Rajputs?