Unfortunately, I don't think the public would have supported that. It wasn't until cases actively started popping up in NZ that people started to understand what was at stake. If the government had proposed restrictions earlier while most of NZ saw the virus as an international issue and not a local issue it would not have been effective. People would have flouted the rules and kicked up a stink about how unnecessary it all was.
I'm not saying we should have gone into a full level 4 lockdown early.
We isolated the people brought back from Wuhan in a separate part of Auckland in early Feb but let people back across the border (even moved the deadline) without having to even quarantine at home all the way up to mid-March, when we knew there was community transmission in other parts of the world.
We were also prepared to hold mass-gatherings right up until the middle of March and only cancelled them at the 11th hour.
That doesn't really gel with 'going hard and early' but people kept saying and no one ever questioned it, and just repeated it until it became unquestionable fact.