One can see grounds for arguing this in recent history, and not just in Hong Kong. But, to paraphrase C. S. Lewis: "Some say that the public is too naive to be allowed to decide. I do not contradict them. But I am still a democrat, because I see nobody wise enough to decide for others."
Plato has been arguing that if you don't select your surgeon or carpenter based on that person's popularity in making public promises, why do you do so for statecraft?
Politicians are elected by their promises, reelected by their performance. Also, there is no objective "skill" a politician can hold to be "good" like a surgeon or carpenter, your analogy breaks down completely.