Yeah you're mostly right
The issues really are the lack of domestically-based content, and the inability to (legally) obtain tv/movie content. Sky TV has the digital rights to pretty much everything you'd want to watch but has no digital download service. Other services, like Netflix, Apple TV and even iTunes are geolocked (I know you can get around this in most cases) which eliminates or limits available content. Other than downloading the odd PS4/PC game, the rest of the web is just fine over my current 50Mb/s cable service. Given our geographic location, latency is more of a killer than sheer bandwidth.
So... Because I'm a (mostly) law-abiding citizen, I can't see the point of being a Giganaire until I can legitimately get video content not consisting of funny cat videos - and that will require someone to bust apart Sky's monopoly.
As far as our itty-bitty little pipe goes, your argument is not quite so clear. NZ is better served, on a bits per capita to the USA basis, than either Australia or Europe. Per capita, Europeans only have about 75% of the capacity we do. However when you factor in that so much more of our traffic has to traverse the pipe we may well be worse off - especially when you consider that Telecoms refusal to use WIX means that a fair bit of domestic traffic has to go to LA and back...