From the paper: "In addition to savings on overheads, a comprehensive database of health-care charges would facilitate detection of fraud, which extracts $85·7 billion every year. Following the transition to a single-payer system in Taiwan, an 8% reduction in overall national expenditure was attributed to the reduction in fraud. By moving from a fragmented health-care payment system to a unified system, irregularities in provider claims can be more easily detected. For example, under the fragmented system excessive claims for physician time can be spread across patients with several different insurance providers. However, acknowledging that improvements have been made in fraud detection since Taiwan's transition, we conservatively assume that the improved fraud detection would garner savings amounting to half that observed in Taiwan, corresponding to 4% of total health-care expenditure."

https://www.thelancet.com/journals/lancet/article/PIIS0140-6...

Aside from decreased executive pay and decreased fraud, many jobs will be eliminated.

From the paper: "Improvements in system efficiency, such as reductions in billing tasks, will involve a contraction of the workforce. Although the country will benefit from lower costs, 936 000 administrative positions and 746 600 positions in the health-care insurance industry are estimated to become redundant. However, detailed transition plans have suggested either funding for early retirement options, extensive severance, retraining programmes, and relocation expenses for all workers in these sectors. Implementation of such a plan is estimated to cost $61·5 billion annually over 2 years, a sum which would be recouped within the first year by the health-care savings estimated here."

https://www.thelancet.com/journals/lancet/article/PIIS0140-6...