Doctors are paid more, but still a small slice of healthcare costs. Doctors in the US working entirely for free would barely make a dent. All administrative costs, including doctors and nurses salaries, but also our bloated health care administration, add up to 8%. A lot of the extra administration costs are also things like all the staff needed just to interface with the giant mess of different payers including multiple private and government programs, all with different documentation and billing requirements.
The insurance companies, pharmaceutical companies, medical device and equipment companies, and private equity owners of hospitals and practices who are all reaping windfall profits at the expense of patients love to direct the blame to doctors though.