Archaeology of the Bronze Age is a crazy house.
A tribe from southern France for one generation, without intermediate stops, moved to Altai (Chemurchek culture). A few thousand years later, some blue-eyed blondes from Western Europe, dressed in tartan, move to western China, where they live without mixing with the local population (Tarim mummies). In the mining area of Southern Zaraglia, in the bare steppe, fortified cities of the Middle East type with clay walls, advanced heating and sewerage systems are suddenly built according to a single plan, and after 40 years people leave them, burn them and burn them unknowingly where (Sintachin culture). Some Altai tribe invented advanced bronze weapons and conquered the territory up to Finland with small drums, and not a steppe belt, like all normal people, but a forest (the Seymin-Turbin phenomenon). These same guys or someone influenced by their culture seem to have conquered China and created the Yin civilization.
As if there is little archaeology, linguistics adds hell. It is impossible to build an unambiguous picture of the division and spread of languages (there are five candidate territories for Indo-European ancestors), and to reconcile this with archaeology - an additional headache (no, for example, no archaeological evidence of the Aryan conquest of India). And now even genetics has spilled out a huge bunch of material, which is completely unclear how to interpret. How do we understand, for example, the presence of the same haplogroup among the higher Brahman of Northern India and 60% of the Kyrgyz people? All the constructions of conspirators of the type "this could not be, because against common sense" go through the forest. In the Bronze Age, everything is against common sense. And not the interpretations of historians, but the starting facts of material culture, linguistics and genetics.
This is my first shock from the most superficial acquaintance with the subject.
Robert Ibatullin