Ofc Mohammed is the most common name but thats a name common within the muslim community. I have noticed the name Sarah in every country, regardless of race or religion. Or it might be an abrahamic religion thing but thats most of the world atleast.
I suspect other Abrahamic names might make the cut.
I don't know the answer, but at least this gives us some way to actually count this:
There'll be a tiny bit of error there, but given that you're focusing only on the most common name, I guess that it's fine.
I wonder if there's some previous research on that. Digging further yielded nothing for me. (You got me curious, too.)
Yeah that sounds like a very reasonable approach. Ofc I'm not gonna do it lol.