That sounds problematic and is only supported by people mindlessly agreeing to it. I know someone who got jobs at google and apple with no linkedin, and he wasn't particularly young. What do you do in the face of it? I say quit entirely. It was an easy decision because I got nothing out of it during the entire time I was on it.
After getting laid off at age 52 (2nd time, 1st time day after my 50th birthday, took an inter-company transfer), and searching for a year, applying to maybe 5-10 companies a week, I got my current job (2 years+) through a random LinkedIn button.
I don't care about how much spying is going on in ESPN. I can ditch it at the shadow of a suspicion. Not so with LinkedIn.
This is very alarming, and pretending it's not because everyone else does it sounds disingenuous to me.