The vaccinated aren't dying from COVID, they are dying from other things because they can't get an ICU bed. ICUs are full of unvaccinated COVID patients, which means all the people getting all the other normal sicknesses are being locked out of medical care.
That's what they mean by "the unvaccinated are killing the vaccinated". People who could have lived if they got ICU care are dying because the ICUs are already full.
My friend's father got pancreatic cancer. His chemotherapy was delayed because the hospital was full of covid patients. Now he's dead. People who get mad about being harangued to take the vaccine are failing to see the whole picture.
That's what they mean by "the unvaccinated are killing the vaccinated". People who could have lived if they got ICU care are dying because the ICUs are already full.