Jainism is believed to be the oldest continuously active religion in the world. Calling it “an outlier” is a No True Scotsman argument. And it’s not the only religion that doesn’t posit a supreme being, anyway.
What’s happening between us is that you’ve been indoctrinated, probably by your family, to believe that Christianity (or something similar) is exemplary of religion; that its arcane trappings and peculiarities are archetypical of religion. To make a possibly improper simile, you’re like a person who’s been raised to believe that all things that are wet are also sweet and carbonated, so when I offer you a drink of seawater it feels like an assault rather than a gift of painful knowledge.
Christianity is a “revealed truth” religion. The way those work is that a person you want to trust provides an explanation for things that seem inexplicable by revealing to you the “real truth” behind the troubling events you’ve observed, or provides a reason to put aside fears and burdens and live a richer, happier life by teaching you that surface appearances are illusory. These faiths typically posit a super-natural or meta-physical reality that transcends mere Nature and physicality.
This is not typical of religion. It happens to be a feature of some very large and powerful religions today. There have always been religions of this type, I think, but there have been religions that don’t follow the pattern all throughout history.
There is nothing mystical, supernatural, metaphysical or inexplicable in my own religious beliefs, which aren’t innovative or unusual. I thought, when I was younger, that I’d discovered the secret of the universe, and was humbled to find that others had already found the same path millions of times.
As mentioned, I am a pantheist. I believe, like many millions of other people, that God is all there is. (Why we believe this is also quite simple and straightforward, and based on science and reason). So - are you reading this? Are my words perceived by your mind? Then you exist. Therefore something exists, therefore my God (and Spinoza’s and Einstein’s and Kneeland’s and Sagan’s &etc.) exists.
You and I are not supplicants before a desert war god who delights in the smell of burning flesh. We are participants in the divine, we are the eyes of the world, our observation of reality literally shapes it. I am you and you are me and we are all together. My God undeniably exists. There is nothing that is super-natural, nothing that is meta-physical, there’s almost certainly no “afterlife” and if something actually happened, it wasn’t “miraculous”, that’s all just superstition.
Edit: Re-reading this I think I’ve expressed myself poorly, but I’m tired so it’s off to bed. Be well and prosper!