Evolutionism tells us there's no necessity for such a concept
As a philosophy, perhaps. But it depends on how you look at it.
We could get all "far out" about it. For example, intelligent life might run in an evolutionary cycle akin to something like Asimov sketched out in his short story "The Last Question". Intelligent life evolves to such an extent that it learns all that is knowable. At that point it becomes God and the cycle of creation begins once again!
Or one might subscribe to the "turtles all the way down" concept of nested universes or gods...
As long as there are ANY questions left to be answered there will always be some form of religion. Furthermore, if the entire universe is indeed God's creation then might not science be a means to better understand God?
When we meet and get to know people we learn more about what makes them tick all the time. In light of this I find it odd that some people seem to have such finite and bounded ideas about what constitutes an omnipotent being!
Surely the true nature of God should fill more than 2000 pages of a single book written 2000 years ago?