Some people need constant vigilance to stop them from embarrassing themselves. Consider Yashodhara Raje Scindia, the tourism minister of Madhya Pradesh and sister of Rajasthan Chief Minister Vasundhara Raje. According to recent reports, she is demanding that people address her as "Shrimant" (your highness) in deference to her family's one-time royal status, with the argument that even in the UK, where she was born, royalty still gets its due.
My feeling is that "your highness," like any nickname, is no good if you have to tell other people to use it. You earn people's respect, and they treat you respectfully. Gandhi didn't have to order people to call him Mahatma and would have impressed me even more if he'd told everybody to call him Mohandas or MK instead a la Peter O'toole in "The Ruling Class". (O'Toole plays a crazy toff who believes he's Jesus Christ, and tells his dad he can call him "J.C.").
Begging--or ordering--people to call you by an outdated and meaningless title that draws attention to the fact that you've inherited your wealth and position rather than earning it just makes you look like a fool. And now, thanks to the Indian and international press, everybody's enjoying a good laugh at her majesty's expense.
BTW: Can anyone really still believe that "your majesty" can be used in any other way but sarcastically these days?