You're right -- the concept is great :). Last time I got an ESTA, however, the site was somewhat byzantine, chock-full of confusing legalese and the response was slow. Comparatively, to get into Europe for 90 days we just have to arrive (https://www.safetravel.govt.nz/travel-tips-travel-europe) -- same goes for Canada.

However, after checking, it does seem like the site has improved a lot. It's been a while :).

The European Union will introduce a similar system, ETIAS, soon. https://ec.europa.eu/home-affairs/sites/homeaffairs/files/wh...

The whole concept goes against the concept of visa-free travel. No matter what they are termed those are effectively – usually automatically processed – visa against the spirit of bilateral visa-free agreements. It used to be that you can turn up at the border to apply for entry there instead of beforehand. Those "travel authorizations" are a step back. Not to mention all the data footprint that this process creates additionally.

Canada does require advance authorisation to arrive by air, the ETA (CA$ 7 online). http://www.cic.gc.ca/english/visit/eta.asp

So it does; thanks! I didn't see any indication that existed on the various NZ government sites about travelling. That would've made for an unfortunate arrival.