That's a good link, but it has some of the usual problems. In the first place, all it does is compare infection rate among some non-vaccinated group before the vaccine was introduced to their infection rate after. That has the usual problems claims of vaccine importance always have, namely (1) they invariably tighten the clinical definition of the disease when they introduce the vaccine (otherwise the people being misdiagnosed before under the new definition but who really didn't have the virus would get the disease in spite of being vaccinated which is embarrassing)
(2) infectious disease rates have been declining for more than 200 years, and they take no account of the background decline which can potentially explain the whole effect.
To their credit they are careful to realize that you won't get a herd effect for diseases like measles and pertussis where the effectiveness of the vaccine wears off rapidly and thus a large fraction of the population even if they are 100% vaccinated Will be susceptible to clinical or subclinical infections. This is why there is no hope of a herd effect for measles and you'll notice they don't discuss measles.