To the Stack Overflow community and Moderators:
Although a lock may be the best option to stop off-topic comments, it's certainly unfair to the OP, as he may no longer receive answers, edit his question, receive on-topic comments, or receive votes. I don't even think it matters if the OP was involved in the discussion or not. We might benefit from looking at alternative methods. One idea off the top of my head would be to lock individual users from posting comments for 20 minutes or so (maybe with the exception of their own posts). There are plenty of different ways to potentially handle these situations.
I think 3 hours is enough time for the users involved to cool down, it probably would be safe to unlock the post at this point.
To ShuklaSannidhya (the OP):
Meta is harsh. Any valid points you may have are easily overshadowed by your attitude and behavior. Don't make accusations, don't call out specific users, and try not to "whine". Just present the facts. I find meta posts are more effective when you ask (Should my question remain locked? What can I do next time to prevent this? etc) rather than tell (This shouldn't happen. My post should be unlocked. This isn't fair! I should have left a rude comment myself! etc.)
If you want better answers, engage with the people who have posted answers. You post is locked so you can't edit it, but maybe in the comments explain why you're looking for another answer. Someone who has already posted one may be able to give you the info you want.