Personal liberty and freedom of expression end at the tip of one's nose. So far as it do not hurt the sentiments of others, there is no problem. But there is no assurance or guarantee, you might have heard how an open letter to PM on Articles 370 was considered as a crime and celebrities were booked for expressing heir opinion to PM through petition.
Narendra Modi is our Prime Minister. But Narendra Dabholkar, Govind Pansare, Kalburgi and Gauri Lankesh were assassinated for speaking against superstition. It is more than 6 years since and the culprits have not been caught so far. Even if you write something against a specifc superstition here I am sure you will get abuses and brickbats.