Before the revolutionary work of Alfred Wallace and Charles Darwin, understanding how complex life could have occurred naturally from simple beings was unthinkable and thus intelligent design/creationism/natural theology were largely held beliefs.
In light of Evolution by Natural Selection, these once popular ideas appear weak, poorly conceived and welcome ridicule. Natural theology poses that a supernatural deity creates an organism adapted to the environment that the deity places it in. The deity creates strong armed monkeys and places them in trees to swing from, for example. What a silly and perverse idea to believe in.
Why would the environment be created in the first place. Surely the environment itself is superfluous? Why not just create entities within a space-less void? Entities "adapted" to not require sustenance. Instantly removing the perennial issue of competing for resources for fear of starving to death.
Thankfully there is now no reason to think there is intelligence to the universe,