Accessory liability generally requires you to know that someone is going to commit a crime, and know that your action will help them.
Juries can make bad decisions in particular cases of course, but if I were the defense I would have a field day constantly repeating the "I can't help you" quote.
The other side would try to say that was just hand waving or insincere, and the jury would have to decide between those two alternatives based on all the facts of the case.
(This becomes a question of fact because particular facts matter. If the Godfather leans in and says the line you gave, for instance, to one of his loyal henchmen, the law should be able to punish him.)