"Skepticism in scholarly circles grew rapidly after 1880. The obvious impossibility of actually locating the Aryan homeland; the increasing complexity of the problem with every addition to our knowledge of prehistoric cultures; the even more remote possibility of ever learning anything conclusive regarding the traits of the mythical "original Aryans"; the increasing realization that all the historical peoples were much mixed in blood and that the role of a particular race in a great melange of races, though easy to exaggerate, is impossible to determine, the ridiculous and humiliating spectacle of eminent scholars subordinating their interests in truth to the inflation of racial and national pride—all these and many other reasons led scholars to declare either that the Aryan doctrine was a figment of the professional imagination or that it was incapable of clarification because the crucial evidence was lost, apparently forever."
January 1, 1970
https://en.wikiquote.org/wiki/Proto-Indo-European_homeland