The potential 'positives' of Islamic heritage were almost always built atop destruction of the Indigenous Dharmic ones. Architecture? Fatehpur Sikri and countless other monuments were built on demolished Jain sites. Mughal painting and calligraphy? It arose after each and every single university-temple such as Nalanda was burnt down along with their manuscripts. The Golden Age of Islam itself had a lot of input from Indian classical knowledge and suspected apostates within Islam itself - both of which met with unfortunate ends.

This doesn't even begin to take into account how many 'backward castes' make up such a huge chunk of India's population not because Hinduism is regressive, but because their ancestors fled into the wilderness to avoid persecution such as Islamic slavery and Jizya! Even Sikhism itself was militarized only with its 6th Guru in order to resist Mughal atrocities. It is the Abrahamic scriptural dogma of saying 'our way is the only way' which led to all this suffering - which Christianity is equally guilty of.

Once history is acknowledged for the sake of truth & reconciliation, we can move forward together. But dehumanizing 'pagans' based on dogma and then denying or downplaying or ignoring their historic persecution will certainly not bring about harmony!