It is about adding code. No dataset will be 100% free of undesirable results. No matter what marketing departments wish, AI isn't anything close to human "intelligence," it is just a function of learned correlations. When it comes to complex and sensitive topics, the difference between correlation and causation is huge and AI doesn't distinguish. As a result, they absolutely hard code AI models to avoid certain correlations. Look at the "[character] doing 9/11" meme trend. At the fundamental level it is impossible to restrict undesirable outcomes by avoiding them in training models because there are an infinite combinations of innocent things that become sensitive when linked in nuanced ways. The only way to combat this is to manually delink certain concepts; they merely failed to predict it correctly for this specific instance.