As someone who attended numerous meetups from the author and saw the vibe among those events, believe me it was as genuine as it can get.
Getting dozens of people in the same room, excited about technology is not trivial, and having hundreds of people show up is relatively hard in a city like Vienna which doesn't have a vibrant tech scene. Sure, some people come to find job opportunities or for free food, but many 'established' meetups sometimes just have a few attendees, so this on its own is not a small task. Peter definitely didn't have time to focus on this given everything else that was going on. So for Vienna, this is pretty much as viral as it gets.
Not sure about other cities where this took place.