“Okay, how so?”
The Mohammedans hold that God dictated the Koran to Mohammad through the voice of the Angel Gabriel. It is actually the word of Allah. So far as I can see, that is precisely the position of many Protestants ( and only Protestants so far as I know) vis a vis the bible, but without the intermediary assistance of the Archangel.
I don't think you have a very good grasp of "Protestant" beliefs at all though your disdain IS NOT hard to miss. Do not the Jews believe that God wrote the Ten Commandments on the stone tablets and gave them to Moses on the mountain? Do they not also believe that God dictated the first five books of the Old Testament (the Torah) to Moses?
The Holy Spirit of God worked through men he inspired and they wrote down the words he intended them to. God himself has seen fit to also preserve these scriptures through the ages so that their truths are still available to us today. It does not matter to me at all what "Mohammedans" think about their scriptures. I have read many parts of it and I am not impressed at all. I see it for the sham it is.
I am sorry you have such little faith in the Scriptures from the only, true God. Without it, all else is shifting sands.