> But one thing I am sure about: no one will notice.
LinkedIn remains one of the largest and best data sets for the recruiting industry. I don't want to speak too broadly since my experience is limited to my current employer and personal experience, but if you remove your LinkedIn you will effectively be invisible to the recruiting agency I work at.
Many companies rely on outbound recruiting tactics since inbound is often too noisy; not having a LinkedIn would dramatically reduce (if not eliminate) the chance of a recruiter finding you without prior contact (referral, application, former colleague, etc). And this is not just limited to recruiters reaching out via LinkedIn. There are companies that scrape LinkedIn and sell that data to recruiting agencies and VC's (and who knows who else).
As an anecdote, having recently complete a job search myself, I have to say that traditional inbound applications (e.g. apply via company website without any contacts) was shockingly ineffective. The difference in traction between self applications using my professional network, job boards, or recruiting markets (e.g. Triplebyte) was night and day.
Since the author seems privacy oriented, removing his LinkedIn is probably the right thing to do, but I don't think it's accurate to imply that there is no opportunity cost to doing so.