Presumably, your referring to the late Queen in terms of "used to be the most famous", means that you're looking for candidates who are still with us. The Obamas have consistently emerged as "the most admired" in surveys in recent years, but that doesn't really equate to "most famous", particularly as they aren't so much in the public eye these days. Trump? If it was "infamous" we're looking for, he'd certainly be a front-runner, along with Putin. The poisonous, arrested adolescent Harry would also be up there with them in my book. Famous? Sorry, but I'm really struggling here. Sad that I find it easier to define the baddies. A reflection of the current state of the world in which we are living? If we extend it to those who have passed, yes, the late Queen would be my choice, probably along with JFK.