VAERS has always had multiple problems.
One: Doctors aren’t required by law to report adverse effects. Many of them wouldn’t risk blowback by doing so.
Two: There is no comprehensive effort to determine whether an adverse effect is actually caused by a vaccine.
Three: Patients can make adverse-effect reports—but are often hesitant to do so.
Four: By far the biggest problem is: most Americans aren’t even aware that VAERS exists.
Therefore, on balance, UNDER-REPORTING adverse effects is the primary defect of VAERS.