There has to be a done of exceptions to this.
You see a cardiologist and they recommend a stent. They aren’t going to recommend a different cardiologist does it.
You see a doctor, and they refer you for a test. They have a share portfolio that contains shares in the facility they referred to.
Medicine is riddled with potential conflicts of interest. Managing them is what professionals are supposed to do and what regulators are supposed to enforce.
I don’t live in the US, I’m a n Mew Zealand. Sadly, I am aware of behaviour that looks like corruption in our system.