"That type of person" accounts for some substantial fraction of the vaccine-hesitant population that accounts for freely available covid-19 vaccines for everyone age 12+ in the US but only 51% of the population being fully vaccinated[1].

So, even if you consider it absurd, this particular belief IS widely-enough held to influence behavior and public policy in the US.

[1] https://covid.cdc.gov/covid-data-tracker/#vaccinations_vacc-...