> Some animals are ready to go as soon as they are born. These are called precocial animals. They are born knowing how to walk.

Early young borns that could walk, like a baby giraffe or baby rhino, often fall down or get exhausted quickly initially; tons of youtube videos show that. Humans are slow learners here, but I would not call these other animals as "born knowing how to walk" if their initial steps are so insecure. Their body structure is different though - a newborn human is basically pretty crap-built. A baby deer kind of is built differently on birth and that also makes sense if you are threatened by other predator animals like wolves or bears or lions.

There's a distinction between having the knowledge and having the physical fitness.

When someone is confined to a hospital bed for months they find that they get exhausted very quickly when they next try walking. It doesn't mean they've forgotten how.