Of course it is if people don't know about it being available. or about the importance of having it (never mind the time and mental energy to get another task done when you're working 3 jobs and have kids to feed). Accessibility isn't just ramps. And the US isn't the only country in the world.
Yes, ant-vaxx propaganda is partly to blame, but this is a much bigger problem that is being deliberately neglected if not actively made worse by those in power for their own benefit.