But the medallion isn't an indicator that you're an expert professional driver. So it's different than, say, an M.D. or a law degree that are required because those things are difficult and the public needs protection from frauds.

Of course, the analogy is far from perfect; in fact, I didn't really intend an analogy, as such.

A degree obviously isn't a license token you can move from one person to another, like the taxi medallion.