It might help to see the world through the view of an infectious virus. Viruses are opportunistic in every way. A vaccine must prevent transmission of viral load from one person to another. Our immune system deals with small amounts of pathogenic substances constantly. We would literally be dead within hours if it didn’t.
A vaccine must prevent infection, either by preventing the virus from accessing cells for reproduction or by preparing the immune system in advance so that antibodies are already present and ready to be manufactured.
A vaccine must prevent disease, in most cases this is accomplished by preventing transmission and infection.
Vaccines are not effective if they fail to prevent these things, as viruses replicate at astounding rates in a diseased person’s body. Every reproductive iteration yields a statistical chance that the virus will mutate in an advantageous way. Because vaccines are static, an advantageous mutation renders the entire population at risk. Respiratory viruses are particularly infectious for three primary reasons. First, they don’t cause debilitating illness before they reach peak viral load in the mucosa. Second, droplet transmission via sneezing and coughing is a perfect method of transmission for fragile viruses that literally die within seconds outside the body, third the mucosa is isolated from the body’s immune response and as such provides a reservoir for the virus to reach respiratory epithelial cells and infect them.
The mRNA vaccines are literally endangering the entire human population in an attempt to save a group of people who have immune systems too weak for survival. I’m sorry if it’s your loved one who is this case, but folks, not everyone is fit for survival. Special accommodations for disadvantaged people is one thing, promiscuous DNA genetic engineering on a global scale is the wrong answer. In the long run, humanity will be lucky to survive this era, we are just one pernicious virus or bacteria away from being wiped out, it literally happens every day to other species on this planet. Why not us?