> I went to school to learn the law. After school I had to teach myself how to be a lawyer.
Boards are for specific specialties. You don't take a board to be a doctor, you take a board to be a podiatrist, etc.
Personally, I think both exams are about protectionism more than anything else.
Source: have taken a bar exam, have a wife that's a doctor.
People interview in most jobs, but people in licensed professions don’t generally have exams testing minimal professional competency in interviews because assurance of minimal professional competency is delegated to the appropriate professional licensing body, which implements entry exams, continuing education requirements, professional complaint/discipline processes, etc.
Minimal competency screening is abstracted out to a reusable, memoizing, component.
Futhermore, you actually practice for several years prior to taking your boards, at which point you submit a representative subset of your cases from actual work, and a bunch of folks toward the end of their career grill you on them, then decide if you pass.