I imagine lot of these would be highly laborious analytical-type roles (staring at a dashboard all day) which don't lead to the high paying and glamorized hacker/pentester roles.
Most places where I've worked only had 1-2 security people that weren't entry level. The majority of people doing cybersecurity work are just going to be looking at automated alerts and automated scan reports, then they pass things up to the senior person to make sure it gets investigated and fixed.