I missed out on the heydey of LinkedIn tech hiring frenzy, because I was just doing my work (on a very small, super-effective team), and didn't want to be on sketchy LinkedIn. Then an SF colleague told me what I had been missing out on, and that other people were job-hopping constantly, and making many times more than I was making.
That job market era is past, but now I think of LinkedIn as a serendipity lottery ticket. Because you're on LinkedIn, some founder or hiring manager or legitimate recruiter doing a keyword search stumbles upon you, some past colleague can see you're available, etc.
(Though the last recruiter I agreed to a call with there sounded possibly delegated to LLM, then said his colleague would be doing the call. On the recruiting firm's Web site, I saw the colleague's title was Customer Success, so the recruiter wasn't even willing in invest in the call like I was. Also on their site, they had an infographic example placement success... and the featured example was into what might be the most infamous tech company right now. I bowed out of that one last week, but I'm keeping the LinkedIn lottery ticket.)