Likely a lot of people just never update their employer on linked in after they leave. Especially if they retire. That'd be a different kind of problem than bot accounts.
I haven't updated my LI profile for quite some time. I don't even care enough to login to see exactly what was the last update. I do know that a recruiter was emailing me about a company that I had already spent time working with and since moved on, but was after I quit updating the LI profile. Still haven't retired either.
