I usually read that in NYC and California the is a LOT of job changing constantly. But when I see a LinkedIn profile there isn't that much job changes in the ex

I usually read that in NYC and California the is a LOT of job changing constantly. But when I see a LinkedIn profile there isn't that much job changes in the experience section. I imagine 20 jobs i.e but I usually see more around 7 or at most 10. Is this really a reality down there? At least for NYC?