Much like political racism, racial racism and gender inequality all result in each other, then racism towards neurodivergencies (regardless of whether in a unstable manifestation or not) results in all the other kinds of racism.
Think of this like strengthening the lines. Anyone pointing fingers at Trump regarding racism can look at their own part in racism to begin with.
By the way this goes for gender inequality as well; any increase in feminism results in an increase in male-chauvinism.
From a material perspective its something as simple as the opinion people carry and the arguments they share that supports other things than what they are being supportive of.
Now imagine the consequence of species racism/viewing cattle as tools for producing milk or calves as beings that can just be dragged from their parents and slaughtered. Hens used for egg-factories.
Its just one of these supreme ethical points: Being vegan.