Read this: https://www.nytimes.com/2021/04/21/health/vaccine-nursing-ho...

"An unvaccinated worker set off an outbreak at a U.S. nursing home where most residents were immunized." One vaccinated resident died.

I hate pay walls...

A more accessible link

https://www.businessinsider.com/kentucky-nursing-home-unvacc...

Some takeaways:

* Elderly, especially with underlying illnesses should be vaccinated.

* One vaccinated elderly person died, though there are not many details in the article.

* 90% or 74 out of 83 residents were vaccinated.

That you haven't met someone who can't take vaccines is not a reason to dismiss them. Intuitively, such people may prefer to stay in self-quarantine to protect themselves, making you even less likely to encounter such a person during a pandemic.

However, getting vaccinated should also help reduce the transmission of the disease to people who haven't yet had a chance to get a vaccination even though they could; the pandemic will end faster than if you let it run its natural course.

For any vaccine (and the corresponding disease) there are people that cannot be vaccinated, but that can have quite severe symptoms (and/or die). If a person is not vaccinated - then this person can spread the disease among those vulnerable people. How this can be problematic - here is an example. One of the reasons Sweden has so high mortality from COVID is that during the first wave elderly care homes were hit hard, because workers spread the virus (mostly unknowingly). That you have not met such people in the last 6 months depends, I guess, on your social interactions style and on the structure of the society you live in in general.