The attention I got through LinkedIn wasn't really worth it. They'd notify me of a shiny new job, I'd notify them of a hard $$$$ salary floor, and they'd laugh their way out of the conversation. Other channels like CodeFights, Triplebyte, and Google's foobar were a lot lower effort and a lot more fun for substantially greater dividends, and now waiting for former co-workers to recruit me is about as far as the search goes.