I don’t know much about New Zealand but I do know that a functioning rail network is amazing(I live in Switzerland and frequently travel by public transport).

My native Sweden had an amazing rail network as well, we even made our own locomotives, but unfortunately it has also been neglected, though not as bad as in Germany.

Don’t diss rail, it can be great.

Rail can also be awful.

New Zealand is largely coastal so ships mostly beat rail. The 3 largest cities have their own ports. Cook Straight separates the South Island from the North Island, which complicates rail down South (apart from the Kaikoura Earthquake totally stuffing it). We don't do many bulk goods (unlike Australia which loves mining).

NZ overall has much less dense population - e.g. Auckland has insanely more urban sprawl than Zurich.

Sweeping statements about rail are a problem here (especially if incorrectly comparing against other populous or landlocked countries), and the biased love of rail makes for wasteful expenditure.