Its something alien to a lot of Westerners and our monotheism, but once you've thought about it in that manner I think a lot of people would benefit from that kind of faithless religion.

The resurgence of gnosticism and its war against God of The Bible (Whom they term the demiurge*) is at the root of many of the evils of today. There is no benefit to it, only ruin. Hegel and Marx's writings are rife with references to it.

Its something alien to a lot of Westerners and our monotheism,

It is not nearly as alien as you would think, it pervades our pop culture. Less overtly common than traditional faith and disbelief and satanism sure. But it has absolutely been explored. If anything it's been explored to death. Yes moreso by japanese media. But the west has more than done its share.

https://www.youtube.com/watch?v=_K5PGWZ0DWI

But that's just a passing reference? Ok sure, let's look at other media then. We've had larger more explicit explorations of it, from Pullman's his dark materials, to the da vinci code, that best seller. And there's a middle ground pervasiveness too, other media like the matrix borrow fundamental aspects and themes from it without being explicitly gnostic. Our media runs the gamut, from mere passing references, to borrowing themes, and outright explorations of it. Media in all genres and for all ages does this.

And that's just the obvious stuff. You'll spot their sophia/hermetic/Gospel of John conspiracies/hermes/isis/owl/minerva/wisdom/simulation/ prison/transformative/strong body-soul dualism... heresies everywhere if you learn what to look for.

Even transgenderism is built upon it. The idea that there is a 'female soul' trapped in a male body. And you'll hear them talk this way, of their female soul and spirit, even if they claim to be atheists. This whole idea depends upon some very gnostic presuppositions, and 'spiritual' ideas. The ideas that the mind and soul are entirely separable, that the body can be a prison, and that there is a force or deity putting souls in the wrong body, presumably for nefarious purposes. The whole thing is built on ancient ideas that do actually pervade our culture. How can you be born in the wrong body if there is not a 'you' separate from your body? And yet it is also 'faithless' for most, they accept these ideas without exploring the metaphysical implications.

I think a lot of people would benefit from that kind of faithless religion.

It brings ruin.

Its the difference between saying "fuck you" to the king, versus saying "fuck you" to any individual peasant. So yeah, the monotheism likely plays a huge part.