This is a stupid conspiracy theory. A very brief check shows the average salary of a doctor in the US is less than $200k annually. The AMA does not have the authority over licensing of doctors to restrict anything.
Deregulating medicine can easily be shown to be a disaster in the making... since the Reagan years, regulations on health care have been relaxed like most other limits placed on corporations and it's led to poor quality care, the highest health care spending in the world, and rent seeking middlemen pocketing billions.
Health care in the US needs to be a government provided single payer system.