For some with naturally acquired immunity, Both costs and benefits are amazingly small!
If you are a healthy 18 year old (infection fatality 1/100,000)[1] w/o vaccine, plus have previously acquired immunity 13X better[2] than a vaccine 90+% effective, you are talking about about 1/ 10s of millions of chance of death or severe complications IF you are infected. This easily puts it in competition with the more serious vaccine complications.
Looking at just two aspects for this hypothetical individual, you could weigh
1/10 million chance of death with no booster vaccine shot VS 17/100,000 chance of bells palsy[3] and a 60% chance of fever, chills and headache.
https://www.nature.com/articles/s41586-020-2918-0 https://www.science.org/content/article/having-sars-cov-2-on... https://www.fda.gov/media/144413/download
>Currently available information is insufficient to determine a causal relationship with the vaccine
is all your evidence for a non-negligible cost this flimsy?
Similar nonzero observations have been made in other national studies with sufficiently large samples.[1]
Some countries have added additional content around it to the prescribing info [2].
Scientific consensus is that the risk is clearly is lower than covid.
Another rare but acknowledged side effect is mycarditis.
We can quibble about the rates but they do exist.
https://www.thelancet.com/journals/laninf/article/PIIS1473-3...
https://healthycanadians.gc.ca/recall-alert-rappel-avis/hc-s...
https://www.aappublications.org/news/2021/06/10/covid-vaccin...