Be that as it may, there is a big difference between not wallowing and ignoring/suppressing something. Especially if you leave Freud out.
https://www.merriam-webster.com/dictionary/suppress
Suppression implies force and a struggle. Its quite different from not dwelling.
I am pretty sure we are talking two ends of the same spectrum with an upper and a lower bound. The reason its worth pointing out is that the simplification otherwise creates new problems due to overcorrecting. While not pointlessly dwelling on negative stuff is certainly good advice, it doesnt mean suppressing negative stuff you havent dealt with is a good idea in the long run. Suppressing the knowledge of information that create negative emotions is a bad idea since its very likely valuable information you will need in the future to not repeat your mistakes. One is a problem with agency over emotions and reactions, one is a practical functional problem.
I think the reference to Freud and suppression might be a not thought through attention grab on part of the authors. Different to what their press statement says, what they have found does not run counter to accepted narratives. While i sympathize with the need for funding, this is a dumb spin.