The most common attack on Medicare-for-All defends one of the healthcare system’s worst features — Some Democrats aren’t jumping to endorse Medicare-for-All. In the most recent primary debate on September 12, Joe Biden, Amy Klobuchar, Beto O’Rourke, and Pete Buttigieg all criticized Medicare-for-All for effectively eliminating private insurance plans, particularly employer-based ones. Republicans, such as Paul Ryan, have also attacked Medicare-for-All along these lines. That…