What's wrong with using Html.map?

Just to be clear, I am definitely not promoting “components”. I also used Html.map AND a (SmallComponentMsg -> msg) together in my example, it was not a choice of one OR the other:

-- Passed in a (SmallComponentMsg ->  msg) arg as toMsg.
someView : (Msg -> msg) -> Model -> Html msg
someView toMsg model =
    Html.div
         [ onClick DoStuff ]
         [ ... ]
         |> Html.map toMsg
         -- Applied it with Html.map