It is evident that being a doctor requires skill; it is not about doing things with finer detail or more force, but about using one's mind, conducting research, and applying clever techniques. The so-called accumulation of clinical experience is the result of doctors using their brains to summarize their work over the years. Therefore, it is not true that all older doctors are good—some doctors work until they are old without using their minds and still have mediocre medical skills.
Some young doctors also make rapid and impressive progress in their clinical work. Why? Because they are good at summarizing clinical experiences, they naturally get promoted quickly.
The laypeople don't understand this; they think it's better to find older doctors. Later on, the laypeople became smarter and realized it was better to look for famous doctors rather than to focus solely on a doctor's age.