Every job that I've had I've found despite LinkedIn. My first graduate job was through word of mouth, the second I was headhunted, the third I found a recruiter that was worth his salt (who also, eventually, placed me at my fourth). Anything I've needed to know about a company there were ways outside of LinkedIn to find out, often as LinkedIn seemed like a HR washed exercise in grandiose. FWIW they're all but one are companies you would've heard of.
What is the value you've had in return from being connected with your previous employers there? I'm connected with my closer colleagues through normal messaging apps.
All my jobs are from LinkedIn, via recruiters for various companies. In fact, I use the number of messages I get per week as a proxy for how well or poorly the market is doing.
What are your experience and interests? Just like SEO, or search engine optimization, there exists the concept of LinkedIn profile optimization. It includes things like having a good profile picture, making sure your profile has a clear niche (fullstack, backend, embedded, etc), having clear bullet points for each of your company experience sections, with numerical values if you have the data ("increased performance by X% using A, B, C"), setting your location to a well-known tech hub, and so on.
Once I did all that, I've multiple gotten daily messages with very interesting offers. LinkedIn is a tool like any other, people simply have to learn how to use it.