My only response is, In taking university courses in anthropology the consensus is that there are ALWAYS exceptions. Of course. But in the main religion practices/rituals are universal.
These haven’t popped up all over the world by accident.
You are focusing on an exception. There are also other universal themes. Flood myths. “The Hero of a Thousand Faces” and “The Mythic Image”
(Joseph Campbell) sp?
The hero has been referred to in The Iliad and The Odyssey.
Interesting is the hero goes on a quest. Separation, initiation, and return. This is a myth that appears in the life of Christ.
There are commonalities across cultures. No culture is identical. What is extraordinary is what evolves in isolation. Similar themes. Common myths.