My guess is that nobody becomes a dentist because they love teeth. They do it to have a stable business. Conversely, people become vets because they love animals, and people often become doctors for the prestige or the ability to help people.
Also in my experience it’s very standard for dentists to quickly go out on their own —- many towns will have multiple dentists and none to one doctor or vet clinic.
Then again I’m seeing places like Aspen Dental popping up all over the place so who knows