Someone fresh out of medical school is a resident so they're under direct supervision for 3-7 years. And unless you live in an area with an abundance of hospitals, there's a large change your local hospital is a teaching hospital staffed largely by residents and the attendings that supervise them. You can request non-resident care only but it's a request and is not guaranteed.
The TLDR is that most people when interacting with anything other than their GP family doctor, are probably interacting with someone "fresh out of school."
So, why do residents need so much supervision? Since they have the most recent, and also usually most extensive knowledge. Granted, specialized knowledge is sometimes acquired during residency. Still, it's mostly taught by attendings instead of being read from books. Medicine is a know-how profession.
You don't learn how to be a radiologist, or an orthopedic surgeon, or an OB-GYN, or any other specialty, in med school. You can't learn surgery from a book. Maybe there are large parts of family or internal medicine you can learn from a book but those residencies are already several years shorter than most surgical specialties.
You wouldn't drop a fresh college CS grad by themselves in a group a developers and expect them to just figure it out. Just like medical school doesn't really teach you how to be a doctor, a CS degree doesn't really teach you how to code. They're both much more academic than the day-to-day of the job you're getting that degree for. They'd still get mentorship from colleagues, supervisors, and others. The only difference is medicine has the ACGME and all the government regulations to make it much more structured than what you need for most everything else.
The TLDR is that most people when interacting with anything other than their GP family doctor, are probably interacting with someone "fresh out of school."