There is a difference between driving too fast around a corner to stop for something stationary on the road and driving through countryside where something might jump out.
I live in a country with deer but the number of incidences of them interacting with road users is so low that it does not factor in to my risk tolerance.
The risks vary with speed. At 30mph a deer will be injured and damage your car, and you might have to call animal control to find the deer if it was able to get away. At 45mph there is a good chance the deer will impact your windshield. If it breaks through, that's how people die in animal collisions. They get kicked to death by a frantic, panicked, injured animal.
I live in a country with deer but the number of incidences of them interacting with road users is so low that it does not factor in to my risk tolerance.