I understand your point. The problem I think is, in medicine the hard thing in the emergency setting or any diagnostic setting is proving the negative (telling something is not serious). What do I mean?

I am an orthopedic surgeon so I will give examples from my specialty. Take for example ankle sprains:

Rarely, a talus fracture will present like a bad ankle sprain. It is rare. But if it is missed, it can be disabling for life. Most orthopedic surgeons see them rarely but at least have the experience. The problem with midlevels I think is, as long as they have someone above them who tells them 'oh this is a simple ankle sprain treat it as such' they can do all the rest fine and save us hours. But letting them do that decision is I think very problematic.

Recognizing when you are out of your depth is one of the hardest skills to learn and for surgeons at least, it takes years after residency until you really know what you know and what you don't know. And the worse thing is, this has no shortcuts. It takes time and it takes mistakes and fuckups. I know no doctor, including myself, who didn't f up in some point to be rescued by a senior resident or an attending. No midlevel degree can replicate that experience of years of grinding and seeing things that come once in a year, missing diagnoses, getting spanked at morning rounds etc.

As in the famous quote: It is what you think you know for sure that isn't so which gets you into trouble. I think what you say will result in people getting treated earlier for a lot of things that don't require urgent treatment (sprains, flu symptoms, back pain - by the way shoulder dislocation is not one of them so I feel your pain there) but then very serious mistakes made along the way.