While I agree that most of the feed is filled with useless posts, for some business sectors it actually contains useful posts.

I work in the European energy market sector and LinkedIn is one of the to go places to catch up with developments in the markets, the latest the analyses, and upcoming events. And some posts are actually good, you just need to filter out the rest. I wish there would be a better platform for this specific content (maybe I'm simply missing it) but for now, I find it there.

Coming from a computer science background and kinda accidentally ended up in energy markets, I was surprised that LinkedIn is the place for this content I(in contrast to the computer science field).