My favorite local meetups fell to problems like this.
It was easy to filter out the DevRel people trying to advertise. The hard problem was filtering out people who were only interested in presenting something so they could show another presentation on their resume or personal brand website, with no interest in engaging with the meetup.
These people would want to only show up for the one meetup where they got to present. They’d present some simple content designed to make them look good, with little regard to educating or discussing things. They’d often have some excuse for needing to leave quickly after presenting, some times before any QA time.
And they always needed a video recording of themselves speaking. For a while we had these to stream to remote viewers, but if the camera gear wasn’t available they’d panic and spend a lot of time improvising a way to record it with their phone even if delayed the presentation. Getting the recording of themselves speaking was the primary goal, not actually speaking to the group.
After this happens enough times, the core members realize they’re being used as audience props for someone’s career advancement and they stop coming. The meetup collapses.
I hope my local meetup groups can have a little resurgence like this where people are primarily interested in the meetup, not the self promotion opportunity.