Normally reporting in VAERS is optional. For COVID vaccines it isn't optional. If you got the COVID vaccine and then an elevator fell on you, they would be required to report it.
https://www.cdc.gov/coronavirus/2019-ncov/vaccines/safety/adverse-events.html
Reports of death after COVID-19 vaccination are rare. More than 414 million doses of COVID-19 vaccines were administered in the United States from December 14, 2020, through October 25, 2021. During this time, VAERS received 9,143 reports of death (0.0022%) among people who received a COVID-19 vaccine.
FDA requires healthcare providers to report any death after COVID-19 vaccination to VAERS, even if it’s unclear whether the vaccine was the cause. Reports of adverse events to VAERS following vaccination, including deaths, do not necessarily mean that a vaccine caused a health problem. A review of available clinical information, including death certificates, autopsy, and medical records, has not established a causal link to COVID-19 vaccines.
However, recent reports indicate a plausible causal relationship between the J&J/Janssen COVID-19 Vaccine and TTS, a rare and serious adverse event—blood clots with low platelets—which has caused deaths. Cases include 5 deaths related to complications from TTS following Janssen COVID-19 vaccination.