The comment you replied to is more accurate, as WhatsApp is huge in multiple continents not just in Europe (just not as big in North America as you both point out). For example it's big in South America (and I think Central America too?)
Yes - I think if you pick a country at random it's more likely to have WhatsApp high on the list of communication tools than not, albeit with some of the biggest countries like China also joining the US in being exceptions).
