[Cronos]

From what it seems they weren't perfect: war enables innovation. The ancient indians didn't war, so no innovations -- it looks like the people who lived there, lived generations in the same house. Things never changed

Why they moved was, as explained in the article, due to the Bronze Age collapse climate change which also brought down the Hittites, myceneans and Middle Kingdom Egypt

The Saraswati river dried up, so less easy farming. People abandoned the cities and either:

1. Moved to southern India along the sea-coast (logical as they were a sea-faring people trading with Sumeria and Elam by sea)
2. Moved east to the Ganges-Jamuna valley system
3. Merged with the nomadic Aryans who were not affected by the climate change as they were nomadic herders

[BobL]

“From what it seems they weren’t perfect: war enables innovation. The ancient indians didn’t war, so no innovations”

I guess it depends on which ‘indians’. American Indians, as far as I know spent much time on the warpath - but it didn’t get them much when Europeans arrived. As far as Asian Indians went - I don’t know enough either way.