in part 5 Socrates makes his effort to discredit teachers as shown below.
“Well, can you name any other subject in which the professing teachers are not only refused recognition as teachers of others, but regarded as not even understanding it themselves, and indeed as inferior in the very quality of which they claim to be teachers; while those who are themselves recognized as men of worth and honor say at one time that it is teachable, and at another that it is not? When people are so confused about this or that matter, can you say they are teachers in any proper sense of the word?”
What Socrates tries to say in this paragraph is that the “teacher” aren’t actually teaching anything to their students. He suggests that they that only teach are taking advantage of those who know nothing.
Then they have a discussion about true opinion and knowledge.
“Hence true opinion is as good a guide to rightness of action as knowledge; and this is a point we omitted just now in our consideration of the nature of virtue, when we stated that knowledge is the only guide of right action; whereas we find there is also true opinion.”
I believe that Socrates was correct by saying that true opinion is and could be helpful but not as much as real knowledge.