I'd have assumed spamming requests and accepting all the incomings would mostly just lead to even more recruiter spam, and that anything else coming through a network so-grown (jobs, collaborations) would be extremely low-value (why would people offer high-quality opportunities to people they don't actually know? Unless they're desperate, which is itself not a great sign, right?)
I have found well-paying freelance and full-time positions recently (~4 months ago) using this exact strategy. I assume that being active daily on LinkedIn will help push your profile to the top (algorithm-based results) over other profiles.
I put my LI profile to "open-to-work" on Monday and had three requests for interviews from various companies/entrepreneurs by Sunday.
The next week, I had at least 4 inquiries about my job status and interview availability. After the 1st two weeks, my email inbox was full of potential jobs/recruiter spam, which I sorted through and followed up on.
I'd agree about most being low-value leads, but getting your resume out there seems to attract all sorts of companies. Sure, I don't want to be a QA or SDET engineer, but my resume helped attract opportunities that I would have followed up on had I been more desperate.
You also have to assume that most recruiters are lazy and are doing the shotgun strategy as well.
If you’re not playing the game willingly, you’re still playing the game.