2. Unknown and definitely unproven
Since 2021 is anomalous and since we have a possible cause... the vaccine... it would be prudent to test the vaccine damage hypothesis.
One approach would be to survey 1,000 people who have applied for disability in the last... oh... 9 months or so and ask 1) are you vaccinated 2) did your new disability start after you were vaccinated? 3) If so, how long after? 4) Do you think your disability is vaccine related?
NIH or the CDC could easily do this. If the results were less than 0.1% yes (1 in 1,000)... roughly 3,000 disabilities since vaccinations started possibly attributed to vaccine damage... then we could eliminate the disability concern.
On the other hand, if it were 10 times higher, that should warrant an immediate freeze on vaccinations until it could be studied thoroughly.