I'm relatively new to all this genetic history stuff, but how valid is this guy's argument on this blog that R1a is more associated with originally proto-Uralic, EHG type populations (and this was also linked to Corded Ware somehow?) while R1b was more Yamnaya and original IE?

I don't know how legit this all is tbh

https://indo-european.eu/2018/09/cor...es-with-yamna/

https://indo-european.eu/2019/05/ste...aking-peoples/

https://indo-european.eu/maps/

And what is the ultimate origin of R1a before it got to northeast Europe and the steppe ? I heard it might have been further south near the Iran or West Asia area, with a few theories even linking it to India, although that is dubious