It’s not an error in VAERS. VAERS is a passive reporting system. It’s designed that way. The purpose of VAERS is not for the general public to browse the reports and jump to conclusions. The purpose is for researchers to be able to identify patterns to locate rare unexpected adverse reactions.
The idea is for people who know how to properly apply statistical models to do so and locate outliers in the data which merit further investigation. Simply pointing out “there are x number of reports of adverse event y in VAERS” to claim a particular vaccine is causing that event is a complete misuse of VAERS. And that’s directly from the creators of VAERS.
Further, the FDA and other independent researchers are absolutely performing the analysis. And they’re providing that information. Where do you think black box warnings on medicines come from? VAERS is one source; indirectly. As for the COVID-19 vaccines, early on there was an unexpectedly high anaphylactic reaction observed (about 1 in 90,000 for Pfizer, 1 in 400,000 for Moderna). This was quickly identified, data published, new protocols (e.g. the 15 minute waiting period post shot) established, and new guidelines issues about who should and shouldn’t get those shots.
VAERS is doing its job, but its job is not to be a clearing house for the public to see the full individual investigation of each report. That would require a lot more work to build and maintain, which means a much larger budget, staff, etc. What exists today is a passive reporting system designed to enable the FDA and independent researchers to perform broad statistical analysis against very noisy data. It’s simply being misused in some cases to scare people about vaccines.