I can't even remember at this point how long ago I deleted my linkedin profile; it was never anything more than a spam factory in my experience. What surprises me is not that they're still terrible, but that they are still - somehow, years later, despite seemingly everyone in the industry knowing they are a complete waste of time - not yet out of business.
It's most astonishing to me that anyone even still uses LinkedIn.
I deleted my account 5 years ago and my career didn't suddenly grind to a halt. Nobody has ever even asked me once for a LinkedIn profile nor turned me down for a job because I didn't have one. I must live in a different bubble from all the people in this thread insisting that it's a requirement at every turn in their lives.
