Famously, lions kills lion babies, that is babies of own species when they encounter babies of another lion group.
The point is that you are at their mercy and that it takes training and education to understand and predict that danger ahead of time. Even adults are ignorant along these lines. Everything is a spectrum, but there is a threshold, in my opinion, in which the probabilities of disaster become 100% out of your control for certain activities.
For example, you can watch this guy on YouTube https://www.youtube.com/watch?v=dV1fzwfJpmQ who appears to be calm and an "expert" on interacting with bears. However, you can also watch this video https://www.youtube.com/watch?v=DqwYUkJYRQc in which a grizzly shows absolutely insane stamina and strength, covering huge distances of rough terrain and water. It means that the guy in the previous video is 100% at complete mercy of the bear, no matter what he says. (As an aside, I'm actually surprised that guy hasn't had more trouble, as he clearly seeks out bear encounters.)
I think my larger point is that part of the education of both children and adults is teaching to understand and ultimately respect the reality in which we live in. Animals, physics, biology, etc. all exist and we must live within those rules and understand the consequences of pushing them. I can't go jump into the sun just to try it out. And a project manager stating a schedule as if it dictates reality doesn't mean it does. Lol. This scene from The Counselor is getting at these lines of thought: https://www.youtube.com/watch?v=EIn7y4ejIFM.
The bison example, I would think any child would be very wary of walking up to a bison. On top of that, if a child were to approach a bison I highly doubt the bison would come out with full offensive. They'd probably assume a defensive posture to scare the kid away. If the kid kept coming you should keep in mind that mammals recognize babies of other mammals. It would be pretty extraordinary for the bison to consider a human child as a threat and attack them.
The cars though, yeah. I don't even want to get into that.