All religions are not timeless whatsoever and will need to be hugely reformed as society and technology progresses.
Religion is beginning to get somewhat outdated, some more than others. But the common ground between all religions is that in highly developed areas of the world, religion is on the significant decline.
Take Norway for example, the perfect example for this. Norway is ranked 1st on the Human Development Index Ranking, and has very happy citizens, the world's most socialised economy, and the world's foremost democracy. However Norway has been heavily declining on the religious side.
Since the last survey taken 2 years ago, belief in god has fallen 4%. Now it's 30%, from 53% 35 years ago. The age group with the lowest belief in god are the 25-39 year olds, with a 19% belief rate.
There are countless examples of this same phenomenon, that belief in god or religion is no longer needed in highly developed areas. It just fades away as a natural process of societal progress, as especially the younger generation discard these outdated ways. And eventually, it's going to be said young people who decide wether to raise a child religiously or not.
There are of course other factors such as the complete eradication of any and all miracles the moment technology progressed and the standard of evidence was raised, and said standard is only going to get higher and higher. Any human raised in a well developed area such as Norway is going to have a significantly higher standard of evidence compared to that of Pakistan, which boasts a 98% muslim rate. And when an entire society has a very high standard of evidence, what's happening to Norway is going to happen anywhere else too.
And these numbers are only going to get worse for religion as a whole in the future. Doubts will be more apparent, brainwashing will be much less common, any benefit from religion is easily obtained without it, miracles will continue to have stopped existing, and negatives will outweigh the positives.
But believe it or not, in our current timeline there are still many people that unironically believe miracles exist, this too is on the significant decline but it scares me that they are still out there despite our progress as humans.
The fatal flaw from the deceptive humans of the past is that religion is stuck at a certain point in time, whereas technological and societal progress is limitless. Something like the creation of a new religion, or even the beginnings of an old one would not be able to survive in our current world.
Perhaps not in my lifetime, but eventually the only option for religion as a whole to survive is to undergo a huge reform. Maybe a new one will surface somehow? It's much more probable than any current religion surviving in the future. Ideally it will just die out, but even in the future religion will still be very useful to anyone in a position of power, so complete death of god and religion is unlikely but still very possible.
Obviously it will take religions with the majority based in very unfortunate countries such as Islam longer to die, but it's only a matter of time in the end.
Anyway, If anyone can let me know of more factors for the decline of religion I'd be grateful, as there is sure to be many more.