I never let anyone else do the company vetting for me, not even for preselection. I also want to have the leverage of negotiating with my future employer / stakeholder directly, recruiter cut including. So from my POV and with all the spam that comes with it, a LinkedIn is not only useless but a major nuisance.

Every recruiter who I connected with via LinkedIn was a salaried employee of the company fwiw. Going around them wouldn't have given me more leverage.

Maybe that changed over the years, I only remember professional recruiters. But even so, this still mostly amounts to noise as to me the majority of companies are just not interesting to work for at all. I usually target 3 to 5 (max) interesting companies / openings which I thoroughly research on beforehand myself. That approach has never failed me so far, keeps me interested and motivated to go through interviewing plus an upper hand during negotiations. YMMV of course, that's just the approach that has consistently worked for me.

Oh yeah there's definitely a lot of noise. I have a niche that is very SEO'd on LinkedIn (Haskell), so that helps. I do just ignore people inquiring about generic software jobs though. But every so often a Haskell company finds me and then I keep in touch.

please email me for haskell help if you do not mind