The article specifically addresses the fact that profit motive alone does not account for the prevalence unnecessary treatment.
Further, only about 20% of US hospitals are private, for-profit endeavors. Over 75% are not-for-profit or government. Of course, they are still affected bybthings like revenue, prestige, "performance" metrics, etc. But Canadian hospitals suffer from those same drivers.
I applaud the work you are doing, but I question your confidence that the US system is the only system with these issues.