Even today we maintain the original homeland of Aryans or watever the west call us is Saraswati belt. Civilisations sprung along river belts and it is an established fact. Most probably the home of Aryans/ Urheimat is Kashmir, Punjab, Haryana, Rajasthan, Gujarat/Sindh. With Kashmir as the most sacred land of Aryavarta. So sacred it is that even those students of Gurukuls from our holiest city Varanasi used to BOW towards the direction of Kashmira in reverance after their formal education coz it is the home of Sharda/ Maa Saraswati. So no, Steppes origin is farce. Kashmir it must be.
Panini is from Swat(named after river Suvastu),in modern day Khyber Pakhtunkwa. Urheimat is Bharat. We went out of India and mixed with locals over there. That's the reason why there never were references of Steppes as our home in Vedas, but we revered Saraswati like some 50 plus times in the same Vedas. Even if the consensus is between Ghagra-Hakkar in India and Helmand river in Afghanistan, still it validates Indigenous Aryan theory. Because, Afghanistan was Hindu for millennia before Zoroastrianism,Buddhism and later Islam took over the reigns.
I need to clarify.
I said both sides do not accept a steppes branch-out ....
That is not the same thing as not accepting a common origin.
Just that our ideas if where the split happened and in which direction.
Hope that clarifies.
Cheers, Doc