In India, many city and street names had been changed by the Mughal invaders during their rule over India from the early 16th to the mid-18th centuries and later by the British. After India achieved independence from the British in August 1947, names of many cities, streets, places, and buildings throughout India have been changed by successive governments to their original names. This process of changing names began as early as 1950 and does not coincide with BJP rule. See Wikipedia (https://en.wikipedia.org/wiki/List_of_renamed_places_in_India) for hundreds of name that have changed since independence.

Regarding one of the cities that you quoted – Allahalbad – its original name was indeed Prayagraj, not “Ilahabas” given by Akbar, which the Mughal invaders changed to Allahabad hundreds of years ago. I don’t see anything wrong with independent India reverting to this and other cities' original names.

You might consider writing an article on the changeover of Hagia Sophia from a museum to a mosque just last week in Istanbul, Turkey. The nearly 1500-year old building had been the largest church for Christians for almost a thousand years before it was converted during the 1453 Ottoman conquest of Istanbul. The secular-leaning founder of the Turkish Republic, Mustafa Kemal Ataturk converted Hagia Sophia into a museum in 1934. It was a beautiful museum with much history the last time I visited it. Now, Turkish President Recep Tayyip Erdogan has declared that it is to be converted into a mosque, and actually led prayers there on July 17.