I think some of the reason may have been that the government was working to fight the spread of disease and our parents who lived through the depression and couldn't always afford good health care readily jumped on the chance for free vaccinations.
The PC debate of choice and personal preferences simply didn't exist then as it does now with every little issue.
Another problem today is the "end justifies the means" strategy that drives liberals to conduct social witch hunts on any issue they come up with. Somewhere along the line the idea that vaccines cause autism pushed by Angelina Jolie seems to have gained a following and anyone who disagrees is a denier; just like with global warming.
We can go back through history and find plenty of liars who became rich and famous as they created a false narrative that took hold with the liberal left and then the lapdog media. Upton Sinclair, Rachel Carson, Paul Erlich and Al Gore come to mind.
Great post.