I like other mythologies because they're interesting, they've got a lot of gods and a lot of other cultures.
Christianity only has Jesus, Moses, God and the Virgin Mary going for it. The mythology is kinda boring and very contradictory of itself. People prefer to cherry pick verses and everything to believe out of than it's intention.
Idk man, when you start looking into the old testament, especially non-official/apocryphal books like the Book of Enoch, it gets pretty interesting. Especially when you take early Judaism in context with the neighboring Canaanite religions
This... might clear things up just a bit. The Book of Nod is loosely Christian/Abrahamic religion adjacent mythology of the origin of vampires in the ttrpg Vampire the Masquerade. It's the in universe origin myth of vampires.
My personal favorite is the Sermon on the Mount. He lays out everything he believes with multiple catchy phrases and in short order. Which is how you definitely know it didn't happen.
I wish I shared your optimism but I fear it is not happenstance that it has survived for so long. I suspect that it contains enough textual material to be easily adapted over time to serve many purposes, fit many cultural mores, and exploit various aspects of human nature.