Why? There’s no definitive proof of any of those things.
Alien life is so mathematically probable that it might as well be proved.
A universe created by a literal interpretation of any religious story is so mathematically improbable that it might as be impossible.
I would argue for a large amount of wiggle room for a non-literal metaphorical interpretation of the various scriptures and religious books of the world.
Discovering that which unites them would certainly be a more constructive past-time than concentrating on trying to prop up the details of any individual credo.
There are understandable reasons why most seek a less prosaic explanation for why we are here and our place in the universe. Science is rarely described in beautiful or inspiring language. I loved Sagan for putting a bit of awe back into the sometimes dry non-religious creation stories of modern science.