It's the same uninspired desperate attempt at trying to get attention by recycling behaviour someone else at some point got views with. Like soy faces on YouTube, or generally SEO / blog spam that's more or less destroyed Google search results.
I'm just honestly shocked that people use LinkedIn as an actual SNS. The only times I ever log in or update my page is when im on the hunt for a new job lol
To get more people to see their posts, some people on LinkedIn follow hashtags and by including a hashtag, that post ha a better chance at being seen by more people.