Gagan Ji,
Since lot of people who have been challaned(including myself) for having a luggage carrier installed on their private cars, are reaching out to you. you are in the best position to seek clarification from Ministry of Transport to get a formal response on this.
A letter from MoT stating "it is legal to have luggage carriers installed on private cars" will be valid across India, across all states.
I sincerely request mycarhelpline to lead this initiative and publish the results in your YouTube videos.
it would be a great help to all of us.
Thanks & Best Regards
V Jain