Well, I completely understand how you feel. LinkedIn was a very powerful portal for jobs and it still is. But like you said, a lot of mixed-multitude are now on there and threatening to take it over. About jobs, people still get legitimate jobs on there, I think the application process is what we often get wrong. Did you know that 99% of jobs advertised on LinkedIn have already been filled up? Before LinkedIn picks up a job, it has already got atleast 200 applications. What I will tell you to do instead is to reach out to recruiters directly. When you see a job, check the details of the company, look for the HR and chat them directly. Else you may be very qualified for a job but your application never gets seen because of your position on the application list.