Why do anti-vaccine people get so upset when told to produce factual evidence?
The problem is that anti-vaccine sentiment is NOT harmless.
Anti-vaccine sentiment means we now have diseases killing children that were effectively eradicated 20 years ago.
Anti-vaccine sentiment means that we don't have a Lyme disease vaccination because the cost of fighting anti-vaxxers exceeds the profit from selling the vaccine.
So, if we look at the balance, anti-vaccination causes real, demonstrable problems while pro-vaccination has yet to have any demonstrated factual downside.
So, yeah, we now have preventable diseases running amok because the logical community was tolerant about anti-vaccination instead of stomping the anti-vaxxers into the ground like they so richly deserved.