Some stars and actors give several titles such a recognisable image that we cannot imagine some other person with such title.
Natasamrat is apt for ANR only and Superstar is most apt for Krishna only. Similarly, Nataratna for NTR and Megastar for Chiranjeevi. No body can dare to use those titles as prefixes to their names to represent their on-screen image.
Even their film titles have become so iconic that if someone tries to use them, their fans will be protesting and abusing the person.
Still Devadas, Majnu, Shankarabharanam, Geethanjali, Ninne Pelladutha, Santhosham, Malliswari, Mayabazaar, Missamma, Vetagadu, Adavi Ramudu have been re-used till now.
When it comes to Megastar titles, people seem to worry about Mega fans as the titles are still fresh in their minds. Recently, they protested Nani using Gang Leader and even asked Sai Dharam Tej to not use Chiranjeevi titles after Supreme.
Interestingly, most of the Chiranjeevi songs have been remixed and Allari Naresh flagged their use much. He even used title Yamudiki Mogudu for one of his films.
Now, Karthi is said to be using Khaidi. Still, Telugu title of the film hasn't come out. May be that's the reason why Mega fans decided to not react.
Somehow, Nani is silent on Gang Leader as he doesn't want to face the wrath of social media again, speculate media people!