I disagree. Annu Malik is full of himself most of the times, but he raises valid points, albeit harshly. Smoking, no doubt has an adverse effect on singing- it hinders the voice quality and it was evident on Prashant's last few performances. An aspiring singer should never smoke. Simple as that.
As for Deepali, while I agree that it was a personal matter, her singing should not be affected by her personal matters and Annu was pointing that fact out.
If you see, Annu scolded Emon for being over-confident, which to me he was to some extent and now he has been concentrating more on singing and doing justice to his songs. Same with Prashant and Deepali. Annu's comments have made these contestants to work hard which has raised the standard of singing in II.