I'm torn on this. Exactly once have I gotten a recruiting email from someone that turned out to be a good match for me. That job literally changed my life.

But... every other recruiting email I've gotten has been at best something I just wasn't interested in, while the vast majority of them are so poorly targeted, I'm embarrassed for the recruiter for clearly not having a clue how to evaluate if a candidate is a good fit in even the most basic ways. All promising job prospects I've had (whether they worked out or not) came through connections, or active work on my part to seek out positions that interested me.

(Obviously everyone's experience differs; I see you mention downthread that you once found a great match from a cold recruiter call.)

So... did that one life-changing job come to me because of a privacy-minefield site like LinkedIn? I'm not sure how that in-house recruiter found me: it was a cold email to an address that I hadn't used in years, and it was just dumb luck that I signed into it a week after it was sent, which seems at odds with the usual way to get in touch with someone you've found through a job-network site.

I'm at a point where I don't think I really need to maintain a LinkedIn profile in order to achieve my employment goals... but a part of me is too afraid it'll be useful (or even critical) to something in the future, so I haven't deleted it. Meh.