Some will watch and wait. On a new patient, you have no idea what kind of patient that person will be. Don’t know if you’ll see them again in six months or three years. That makes some dentist much more likely to be a bit more aggressive rather than take a “wait and watch” approach. Otherwise, those small undiagnosed cavities that the dentist said look fine are now root canals a few years later.
Also, retiring dentists are often pretty burned out and lazy in their later years. I wouldn’t get another opinion just over this. If you like everything else about the office and the dentist I would stick with them.