I edited the comment after they replied

I added “assuming” after they replied

They obviously dont cause autism. But even if you ignore everything people who know things about the subject say, it still wouldnt make sense to claim that vaccines are bad

I dont understand people claiming vaccines cause autism. Assuming vaccines caused autism, it clearly has a small chance since most people are vaccinated. If they didnt prevent diseases, why would so many people promote them? If they did prevent diseases, do the people claiming vaccines are bad prefer their child dying from a disease more than their child having autism?

Edit: added “Assuming vaccines caused autism,” to reduce confusion