A spin on the old saying...it's NOT what you know
As a long time shameless self promoter, I add a third point.
"It's not what you know, and sometimes it's not who you know - it's who knows you!!" It seems some people will brag about how many contacts they have and surely that will keep them busy following their social media posts, but how much do they really know about you?
Do they know enough about your goals, skills and passions to think of you when the time comes to refer you for an opportunity? Do they even have a copy of your most recent resume? I was amazed that my own husband couldn't really describe to others what I did for a living. I was Facilitator and all he knew was that I facilitated something. It was my fault that I had assumed, based on all of our conversations, that he really knew my role, but I had neglected to empower him to promote me and my skills. Believe me - he knows now. :-)
I also know that a lot of us don't feel comfortable "selling" ourselves but how else will they know to contact us when we are their employment solution? Just think of it as sharing information. The next step is to give them reason to promote you. I have gone so far as to tell my network that every lead equals a free coffee from me. Next thing you know I am getting pre screen contacts to follow up on. Hope this helps.