That's an extraordinarily disingenuous take on that comment. They were clearly referring to the decision to mess with the code in this way at all, not the actual content of what was being displayed on screen. The point was obviously that deciding to use this method to cause this amount of effort/trouble and mess with the computer system belonging to someone else is the act of bad judgment. The fact they chose to do it with white supremacist messages is irrelevant to the original comment.