Double Nat on one side is not that universal. Across Europe and Australia I've seen it maybe once on a residential connection. I'm sure it's used, but the comment about the US in the post above just doesn't match my experience.
Great for you for not having to experience it, but that doesn't mean it sucks any less for those less fortunate:
> Our [Native American] tribal network started out IPv6, but soon learned we had to somehow support IPv4 only traffic. It took almost 11 months in order to get a small amount of IPv4 addresses allocated for this use. In fact there were only enough addresses to cover maybe 1% of population. So we were forced to create a very expensive proxy/translation server in order to support this traffic.
> We learned a very expensive lesson. 71% of the IPv4 traffic we were supporting was from ROKU devices. 9% coming from DishNetwork & DirectTV satellite tuners, 11% from HomeSecurity cameras and systems, and remaining 9% we replaced extremely outdated Point of Sale(POS) equipment. So we cut ROKU some slack three years ago by spending a little over $300k just to support their devices.
