The industry is moving in that direction as well. Nurse practitioners are now the common entry point into the medical system, with doctors reserved for follow-up. Even LPNs are being phased out in favor of medical assistants.
Also non-doctors have a much higher usage rate for expert systems and data entry systems. and their work patterns are usually highly formalized and verified by expert docs.
So in practice , non-doctors might be able to offer better medical treatment , than you average doc.
I think the vast majority of times one needs to use the services of a doctor could be handled by someone with far less training and certification.