> If there were significant negative side effects of vaccines - of an order which negates the benefits of those vaccinations - I would argue that we'd know that by now.

New vaccines are created and may have side effects. E.g. H1N1 vaccine causing narcolepsy in Europe recently: https://www.cdc.gov/vaccinesafety/concerns/history/narcoleps...

Using the phrase "the science is settled" is silly, given that the creation and manufacturing of new vaccines isn't settled.