I have been asked to sign up for LinkedIn so many times I can’t remember. I just ignore all the requests, frustrating all the people and dashing their hope of using me for their own purpose. Don’t waste my time with Facebook and this phony “like,” “dislike,” and “friend” nonsense. All just another way to use you and get you to use it. Same with “followers” on Twitter. These people know it but humans have their foibles and every one of these “social” media exploit it.
Yes, I have somebody who pestered me over LinkedIn too. Like you, I ignored all of it.
His claim was that it “made me real” - puhleeze.