The Economist's analysis creates a model that shows Pharma companies making "excess profits" (greater than 10% return on capital) second only to technology companies. In that sense, by the Economist's terms, they are in fact gouging.
But that's not really the point the Economist wants to make; rather, regardless of whatever profits Pharma is raking in, they're in fact a small component of overall health care spending. You could zero out Pharma profits (this is my point and not theirs) and not materially change US health spending.
In all these discussions about American health care, my first take is that everybody should go download the CMS National Health Expenditures, and make a beeline for "Expenditures by Type of Expenditure and Program" (it's just an Excel spreadsheet). It's an extremely intuitive breakdown of where all US health care spending goes, and who's paying for it, all on one sheet.
There are a lot of narratives about health care spending that do not survive first contact with that spreadsheet.