I believe this is incorrect. The required proportion of the population that needs to be immune to get a herd immunity effect depends on how infectious the pathogen is. Measles is really infectious with an R0 (number of secondary infections caused by a typical infectious case in a fully susceptible population) of over 10, so you need 90 or 95% vaccination coverage to stop it speading - and why it didn't much of a drop in vaccination before we saw new outbreaks.

R0 estimates for seasonal influenza are around 1.1 or 1.2. Vaccinating 100% of the population with a vaccine with 60% efficacy would give a very large herd immunity effect (toy SIR model I just ran says starting with 40% immune reduces attack rate from 35% to less than 2% for R0 1.2).

(Typo edit)