No, the fact that people have grown up to very limited or even arguably nonexistent consciousness, but still perfectly functional, capable and alive, means that. Functional enough to survive 7+ years by himself in a French forest. Add that these cases prove that perfectly healthy and normal human minds might never achieve consciousness, or at least nothing exceeding whatever consciousness a cat or dog achieves. There was no medical problem preventing consciousness, we don't even really know what the problem was, or perhaps I should say which of the many, many problems this child faced caused this. Lack of human contact ? Upbringing by wolves (assuming that actually happened) ? Was it surviving by himself ? Was it the water ? Perhaps a forest is just a uniquely bad environment for kids ? Perhaps even that specific forest ? Perhaps there was a human or animal or even something else in that forest that somehow further traumatized this kid ?

You'd have to give definitions of consciousness that don't include human contact, don't include language, symbols, any human other than yourself at all, or any thoughts at all not related to short-term survival, don't involve realizing you (as a human) are obviously not a wolf, ...

It also means that there is a period where you can be taught consciousness, and clearly if it doesn't happen before 7 years of age, you will never learn it.