That was the charlatan crap that took over in the last 10 years. Once upon a time, people actually cared about tech for it's own sake, and spent time geeking out and having meetups for the fun of it. Not everything was a "networking opportunity" to grift into a 6 figure PM role. I'd say 2014ish was about the time those things started becoming >50% nontechnicals and recruiters, which was about the same time that every last drop of real culture in that city made an exodus to the east bay.