Well, those 2 criticisms are true. You can test that out yourself.

What’s missing is that lots of things in your home are bad in water and are flammable. But how often do you need to save a baby from an evil villain by tossing their little box into a river and hope a nice childless couple who always wanted a child finds them and raises them as their own?

Situations where the material is a liability are few and far between.

as my dad loves to say, 3000 years of chinese medicine _can't_ be wrong

The maternity kit includes more than just the box itself, which (along with concurrent economic development and other changes) confounds study of its effects.

In fact, with imitations of the maternity kit (or just the box as a sleeping spot) becoming more popular outside of Finland recently, often boosted by marketing playing on the correlation of the kit and the decline in infant mortality in Finland, a number of health entities in recent years have raised concerns that the box-as-crib itself may be a safety risk rather than an aid.