This is a rather abrasive way of putting it that tries to communicate this point. I would have found it difficult to even entertain when my Gopher squishee on my desk and I came across it as someone very in love with Go at the time.
The point though is that for loops in Go are unstructured, but very flexible. That lack of structure lets you have any organization you have, probably influenced by previous languages you've used.
Structured recursion like folds and maps enforce a certain pattern to this, the same goes for traverse.
That idea isn't specific to traverse though, it generalizes to all of the Haskell abstractions. The reason people talk about composability so much is because composable code means re-usable, concise as in KISS , and elegant code.