Do you think in that universe there exists pamphlets and books published by the hate group as guides to why mutants were not human like saying "the mutant is a parasite among the earth"? i mean similar to how back in real life in the US in the 19th century when Buckner Payne in the south published a book as a guide to why people of different skin color were not human even saying things like "the negro is not a human being, but one of the lower animals" as it had a picture of a black man pictured among apes and monkeys. Plus i'm sure back when they had anti-mutant laws before acceptance it's similar to how in the US in 1857 when the supreme court said "the negro is not a person in the eyes of the law! a subordinate and inferior class of beings". Or similar to in the 1930s/early 40s WWII in Europe when Hitler said "Jews are a race but not human" plus how Hitler and the Nazis published propaganda films/pamphlets as guides to why Jews were not human even saying things like "Jews are parasites in the nations of Europe" even "Jews are rats".
Afterall in the past X-Men stories were metaphors to real life history like US slavery to 1930s/1940s holocaust/WWII europe times of anti-semiticism and i'm sure in the Marvel universe, Graydon Creed and his members of that hate group made similar anti-mutant propaganda guide books like to the real life events in the 19th century America or in the early 20th century Europe.