The Kiwi accent is quite different. It's certainly closer to your typical southern English accent than a US Midwestern one, but the vowel qualities and rhythm of speech are completely different from both. As somebody from Ireland, I don't have issues picking out somebody from NZ. I could understand getting a New Zealander mixed up with an Aussie if you don't notice with differences in vowel pronunciation between the two countries, but that's about it.
That said, both AU and NZ have their own "TV accents", which in AU is referred to as "Cultivated Australian", which is relatively close to British RP (though not the same), and I expect NZ has their own equivalent, but most people would have something close to what you would generally think of people from that part of the world sounding like.
In tech you'll run into at least a few during your career. If you lived in Asia, you'll probably see more than that (more common than Australians for some reason).
Uh? I get saying its resembles more of a midwest Canadian slant than sounding like pure midwest American english, but Southern English? Having lived in Mississippi and worked with plenty of New Zealanders, I don't see that.
I think the parallels that people draw with the American south are typically the northern UK, like the Scots Irish.
In terms of US-UK parallels, there's also the effect that geographical isolation has in making a sort of language "time capsule" where colonies stick with dated pronunciations or vocabulary. I've heard an attempted reconstruction of London accents from the early 1700s that sound a lot like General American or Canadian English. The same source had an early 1800s reconstruction that sounded rather Australian to my ears. One imagines that English people colonize either place at a given time, leave some trace of their time and place in speech patterns, and their relatives in England
go on to evolve speech patterns in different ways.
Non rhotacism (lack of pronunciation of R) also left some traces in the American south (and northeast). That feature began in southern England after colonization, so I believe it was generally fashionable people keeping up with the latest English trends who brought it west.
That said, both AU and NZ have their own "TV accents", which in AU is referred to as "Cultivated Australian", which is relatively close to British RP (though not the same), and I expect NZ has their own equivalent, but most people would have something close to what you would generally think of people from that part of the world sounding like.