The ideas that I see in Islam, Christianity and Judaism, from the virgin birth, to the afterlife, to even the Satan character, can all be traced along trade routes. The people who wrote the Bible and the Qu'ran certainly had heard of these earlier ideas from travelers or worldly members of their communities.
There are ideas in Islam that can be directly found in writings from polytheistic religions far before the discovery if Islam. However, these ideas are all derived from religions that are connected to the Middle East, you have virgin birth and resurrection from the dead for example which can be traced far back. But you don't have reincarnation, or a world turtle which are equally ancient beliefs, but aren't from cultures that the creators of Islam would have had contact with.
You obviously believe in the religious narrative, and I am fine if that makes this word of god thing make sense to you.
But to me who doesn't believe in the word of god, seeing how these religious ideas were developed by people over generations and passed along trade routes is more than a coincidence.