I don't mind a proper em dash (w/ width equal to full height of the font), which is what the original headline had. Somehow it got changed to an en dash in the

I don't mind a proper em dash (w/ width equal to full height of the font), which is what the original headline had. Somehow it got changed to an en dash in the HN headline, which has only half that width. Unfortunately, there are annoying inconsistencies in how different software selects an 'appropriate' dash, so I agree: better to avoid them.