The law of back reactions in bitcoin.If a bank transaction was sent to a wrong account, that transaction can easily be reversed by the help of a customer service. It will be a plus to blockchain if a mistake in transactions happens like sending coin to a wrong address and it can be reversed.It will be nice if that can happen, Some many people here have really lost some money because of some mistakes in address.
If this feature would happen to be implemented, more people would lose money to scammers than people have their lost coins returned. PayPal does have chargebacks, and it's a massive problem for merchants, because scammers abuse it. And Bitcoin's pseudonymous nature already attracts scammers, so with this feature we'd have even less adoption, because sellers will have another reason to refuse to accept it.