Yeah, two-year-olds love to put random found objects in their mouths, often accidentally inhale them, and often lack the correct throat motions to unstick a round object.
They said that most just pass though the digestive system, I was special
Would there be downsides outside of manufacturing cost and having to design with the hole in mind ?
It takes a long time before any of the other senses become mature enough to be (more) useful avenues of accruing information and parents can finally stop worrying about it.