I think it's more about the UX. I don't actively use either platform but the experience of asking "I wonder where my friends are", going to a map and going "huh

I think it's more about the UX. I don't actively use either platform but the experience of asking "I wonder where my friends are", going to a map and going "huh, I guess I know someone currently in XYZ place" is pretty different from having to search for a place.