Being anti-vax is a luxury position for people living in a place full of vaccinated people who want to signal that they are non-conformist and don't kowtow to the elites. Holding this position has zero cost as long as everyone else around you gets vaccinated (in fact, it's net positive, since you save the bother of actually getting vaccines). The cost/benefit analysis will change once enough people adopt this position and herd immunity dissipates. How many dead/mutilated children it will take to reverse course is unclear.