It's because, in retrospect, now that the vaccine was extraordinarily successful, people realize how stupid you anti-vaxxers were, so it seems dumb to pander to you now that you've already been proven wrong and humiliated.
I still remember a time not too long ago, during my childhood 40 years ago, when not vaccinating your children shortly after they were born, would raise eyebrows, and society, in general would frown upon the parents. Today, due to misinformation campaigns, and the absence of critical thinking, the anti-vaxx movement has flourished, resulting in thousands of needless deaths in North America, as well as an increase in diseases like measles, once thought to have been virtually eliminated.
The anti-vaxx movement hates children.