It's just about looking for cause and effect. Dravid's being left out of the team since Dhoni took over (which, in any case, only partially accounts for the massive statistical variation between Indian success with and without him) coincided with India becoming bloody good. Or was it a coincidence? What changed in between the 4-2 home defeat to Australia and the CB series that made India a stunningly good ODI side?
Here is the third ODI of the 4-2 defeat, which India lost by 47 runs.
Here is the first CBS final, which India won by six wickets. Praveen Kumar and Ishant Sharma came in for Sreesanth and an injured Zaheer Khan, while India dropped Rahul Dravid for the series, playing Pyush Chawla in a five-man attack. MS Dhoni was captain, as he had been during the Australia series. I'm also missing out a successful home ODI series against Pakistan, in which Dravid played no part.
Starting from that victory, India won eight out of nine ODI series, whereas prior to it they lost in England and flopped in the world cup. What changed that made India so damn good? Would you propose that Dravid's omission had absolutely nothing to do with it?