I suppose my main issue is that I just don't think the passage of time since the mid 19th century is long enough to give a natural selection answer for humans. Perhaps it might be more believable if Holland had suffered great loss of male life in WW1/WW2 and smaller men were disproportionately affected leaving tall men to breed widely. But Holland wasn't in WW1 and its loss of life in WW2 was relatively light.