It sounds like you haven’t spoken to actual doctors and this is all observations from outside.

All the doctors I know of are constantly learning, even outside of their legally mandated continuing education. I don’t know any that aren’t curious about new drugs and treatments.

It sounds like maybe this is just bad communication. The writer of the article was talking about something they had seemingly read in popular media about regrowing teeth. It is not yet possible to regrow teeth in any sort of meaningful way. The doctor will almost certainly have known that. Even if they don’t know anything about it, you can’t regrow teeth so what is there to learn?

If someone came to you and said: “I heard that AI can build a $1billion business with no human intervention”, you might similarly roll your eyes and keep going about your day rather than try to explain why that brushes with reality, but isn’t.