Scientific medicine (I mean of the particular western variety practiced in the US) has a short history, less than 150 years. Scientific medicine without the overwhelming influence of profit had an even shorter history, and it's been over for a while now.
The reason that the now shown to be fraudulent study in 1998 still provokes enough concern among parents to prevent them from getting their children vaccinated, even in the face of massive evidence that there is no link between vaccines and autism, is because many people simply don't trust medical science.
Why don't people trust medical science? One basic reason: medical science is corrupted by the pursuit of profit, and people know it. One fascinating study showed a bias in the publication of research that put into question the efficacy of depression pharmaceuticals. Drug companies (and device manufacturers) are most often the sponsor of research, as our government and institutional research budgets dwindle. (But we get a lot of fighter planes and big university stadiums, instead.)
Things that happen when research is corrupted by the influence of profit: Diseases that don't have treatments that can be profitable (mostly because not enough people have them) simply aren't researched. Bias means the efficacy of a (sometimes expensive) treatment is overestimated, certainly in comparison to a treatment that is not profitable. Alternative treatment methodologies (chinese medicine and ayurveda, in particular, which have long histories) are not researched, and not covered by insurance. Treatments, vaccines and devices get put together in the cheapest ways possible, which can lead to unintended consequences. Medical care becomes impersonal and prone to error.
Basically, we've broken health care because we've allowed profit-making entities to warp it. And nothing short of a 100% government funded research program, and a single-payer health care system is going to change it.
Based on evidence, if I were a parent, I would vaccinate my kids. And I do wish that more parents would talk to older people about what it was like before vaccines. But really, I don't blame people who don't trust medical science and/or our health care system. Because despite some true breakthroughs, they just aren't trustworthy.