Jackson was wrong in saying they do not punish the wrongdoer--yeah, they can't stone people, but they do shun and this form of punishment causes psychological trauma that can lead to physical manifestations.
New research coming out in psychological literature points to the "nocebo" effect, self fulfilling prophecy that telling someone they are no good may lead the person to actually do bad and suffer consequences, and also lead to all sorts of mental turmoil and stress.
JW/WT doctrine and procedures regarding DA/DF'ing do cause harm and they are indeed a form of punishment, perhaps even causing a greater degree of anguish and suffering for a long period of time.
Excommunication from the Catholic Church doesn't carry the penalty of forced shunning on the part of family and friends. And yet the WT saw this as barbaric and pagan, not for the Christian congregation.
The WT publishes contrary ideas quite often, and followers are expected to live with this disonance of conscience and beliefs all along following and obeying every interpretation and publication by the Gobbering Body and its helpers.