Here is what one wise soul wrote, on the subject of AIT and OIT (and recent Antolia -as origin of PIE/agriculture etc.)
Anyhow Nilesh ji, the problem is:
1. OIT needs to kill AIT
2. AIT is tied up to Linguistics only
3. Linguists bring in Archeology (in fact only the Cabalus Horse) because they cannot take AIT much beyond 1500 BC because they are hamstrung by the circular argument in the case of ‘Sanskrit, Old Iranian, Mittani, Akkadian conundrum’. Basically they want to avoid having to move dates. Latest ideas like tying language to agriculture is basically to creat more horse arguments.
4. Ergo AIT needs to shift the onus of proof onto OIT people
5. Unfortunately for them OIT does not require Horse.