So, is violence never OK, regardless of provocation?
If a parent smacked a child I would back the child if they hit back in self defence. Nobody has to be the first one to hit, and as their care givers, we should not be teaching children that violence is the answer whwn you are in a disagreement.
If you were to hit another adult (not in self defence) it is assault.
If you are to hit your partner, it is assault.
If you hit your elderly relative with dementia, it is assault.
All of which you get prison time for. So why is it remotely ok to punish children with physical discipline?
So does confiscation of toys teach kids to steal, or sending a child to their room teach them to ostracise other children?
No. It teaches that actions have consequences. If you misbehave, you lose access to a toy. If you behave well, you get access to it. If you're having a hissy fit and can't be reasoned with, you go to your room until you have calmed down, and will resume talking when you are not in an extreme emotional place.
Taking away an iPad cannot be compared to stealing when the parent has bought it in the first place.
It is the smug superiority, based on zero actual evidence, that grates.
If you research it there is a lot of evidence in regards to the psychological effects of physical discipline. Conditioning to think you deserved to be hit, compliance through fear and damage that does to self esteem.
Imagine a man/woman is in an abusive relationship. Their partner hits them and gaslights them, saying you made me do that to you because of x reason. If they've been conditioned in to fear based compliance and also thinking they deserved to be hit, they will probably roll over and take it for many years until either they question it and try and summon the courage to leave, until somebody points it out, or until something worse happens to them.
Somebody who has been taught that it has never ok to hit somebody (unless in self defence) is much less likely to do so. They are also less likely to be physically violent themselves.