"Overall percentages [of steppe ancestry] are generally very low, and in South Asia also too late for a plausible first arrival of Indic languages here (let alone Indo-Iranic as a whole). But however small and late, and however implausible that they replaced all languages from Iran right across to northern India, that is what has to be claimed for these weak signals, for the Steppe hypothesis to be right."
January 1, 1970
https://en.wikiquote.org/wiki/Genetics_and_archaeogenetics_of_South_Asia