Most people randomly accept invitations on LinkedIn: "We're both humans, so I felt we should connect!".
But if you actively prune / curate WHO you add to your LinkedIn, you end up with a feed that is genuinely useful.
What you do need to know is WHY you want to use LinkedIn. It could be to find your next job, finding potential customers, or just keeping up to date with <INDUSTRY>.
You don't need to accept at random. I'm selective - I only connect with people I worked with or know well from the industry - and it's still 99% AI slop.
Part of the problem is the tech industry. There's plenty of people trying to get rich quick in tech and LinkedIn is essentially made for them. I don't see it as much in other fields where most people don't imagine themselves building unicorn AI startups with VC money and becoming obscenely rich.
It is a way to keep up with opinions about industry news, but at least for tech, I think this is all downstream of what's happening on "short-form" social media. It breaks on Twitter and then you get LLM-powered thought leadership on LinkedIn for the next two weeks.
I used to accept only people I worked with/met in person, but the feed is crap anyway so why bother. I now accept pretty much everyone and prune the feed.