No prob. To clarify, because this was asked offline: DAGs are helpful regardless of whether one chooses to use propensity score matching (PSM) for the problem at hand. What the peer reviewers are likely trying to understand is why we used, for example, standard multivariable outcome regression instead of PSM. Good discussion on pros and cons in this datamethods thread.
Another recent peer reviewer comment was that because DAGs are not a routinely used approach we should explain their differences from more standard methods such as decision trees. I literally had to google what decision trees are supposed to be in this context…