I think the responder means that duplicate code is usually easy to refactor into single methods. Typically I see copy pasted code that is changed just a little bit. However much of a duplicated function can be broken into smaller functions and the redundant code removed in favor of calling into the functions. Often what is left then becomes easier to reason about and refactor accordingly. I love the PRs that I make which delete more code than I add but still manage to add functionality. It doesn’t happen often but it’s fun when it does.
Similar to the concept of asking why five times, there’s an idea that who you ask should also be six levels deep from the CEO. You’re not going to be able to know everything so cultivate contacts in low places. There are the people that are closest to the problem and have the best answers.
From a more hands on side, perhaps you can convince your boss to let you embed in different teams for a sprint once per quarter.