not sure if it's the case, i think they can notice things but they quickly forget or go back to mainstream views if what they noticed are against it. a great example was that in 2015-2016 i started mentioning every time a muslim terror attack happened in europe, to my father. 99% of these attacks were never mentions on tv which is the only place he got news from. he quickly became based and started hating muslims. then i moved out and couldn't supply him with nearly daily updates on the eu and in less than 2 months he was back to the mainstream view of  muslim = religion of peace  refugees = welcome as soon as his only news was from tv again he went back to that programming. so i believe it's more likely that they just aren't interested in seeking out the truth and anything that hasn't happened recently is quickly forgotten.  that said, some low iq surely have bad pattern recognition, but i don't believe it's the main problem with npc's
Denmark