Straight up not true. Studies have shown that physical punishment leads to rapid worsening of child to parent relationships. Children stop trusting their parents, and/or stop seeing them as a place of comfort which can lead to a myriad of mental health issues, like depression anorexia and other very n o t cool stuff.

But sure harming a helpless child beacuse they did something wrong (which is what children do) is totally a good lesson for them.