It was a counter argument, also it was to give slight insight as to what you're supposed to do because some people complain about how things are weak when they play it wrong.
Also the Arsonist thing would be useless, and it appears that it will be a kind of troll option. It does not help the Arsonist whatsoever. Does the random guilty voter dies for Jester change anything? Yes, it makes the town not want to lynch him. If the Arsonist had this option on, he could just claim arson and say, "Oh I'm Arson and you can't lynch me or else all my doused targets will die, so instead you have to let me finish dousing the rest of you so you can die anyway."
There is absolutely no problem with Neutral Killers right now.