Indeed, if one accepts that the migrations of Indo-Aryan speakers into South Asia already entered the realm of mythology at the time of the Rgvedic h… - George Erdosy

The idea has recently been challenged by archaeologists, who ― along with linguists ― are best qualified to evaluate its validity. Lack of convincing material (or osteological) traces left behind by the incoming Indo-Aryan speakers, the possibility of explaining cultural change without reference to external factors and ― above all ― an altered world-view (Shaffer 1984) have all contributed to a questioning of assumptions long taken for granted and buttressed by the accumulated weight of two centuries of scholarship....

As for Burrow‘s thesis that some place names reflect the names of geographical features to the west, and thus preserve an ancestral home, they once again rather rely on an assumption of Arya migrations than prove it. [...] His cited equivalence of Sanskrit Saraswati and Avestan Haraxvaiti is a case in point. Burrow accepts that it is the latter term that is borrowed, undergoing the usual change of s- > h in the process, but suggests that Saraswati was a proto-Indoaryan term, originally applied to the present Haraxvaiti when the proto-Indoaryans still lived in northeastern Iran, then it was brought into India at the time of the migrations, while its original bearer had its name modified by the speakers of Avestan who assumed control of the areas vacated by proto-Indoaryans. It would be just as plausible to assume that Saraswati was a Sanskrit term indigenous to India and was later imported by the speakers of Avestan into Iran. The fact that the Zend Avesta is aware of areas outside the Iranian plateau while the Rigveda is ignorant of anything west of the Indus basin would certainly support such an assertion.

For example, Erdosy (1995) noted that cremation was pretty common in 2000 BCE Balochistan (Penano Ghundai II, Mughal Ghundai III, Dabar Kot, Mehi, Sutkagen-dor) but very rare in Central Asia: “If anything, on present evidence, cremations appear to have originated in the Indo-Iranian Borderlands and spread northwest (and southeast) thence, against the grain of postulated movements of Indo-Aryan speakers”.