Grown cats can suffocate a baby, but small kittens most likely won't.
It's not that you should "keep them away" it's that they shouldn't be left unsupervised.
I think this image is setting a dangerous precedent. These cats will grow rather quickly and believe it's okay to hop onto this child's head and take a nap
Cats the biggest issue is it sleeping on the child's head and suffocating. Otherwise most cats are more likely to run if the kid did something exception being a scare scratch result