So redundancy in New Zealand is: 
At the moment, lump-sum payments are treated as income in the year in which they are received, and taxed in one hit.  
Indeed you might jump TAX brackets if you are a lower earner you lucky ...... and pay more than your usual TAX.

Meanwhile over in the workers paradise Australia ....   TAX free up to a certain level per year ...
Gives you a bridge while you find new employment.

Seems our laws are a bit off ?    

"" From Aussie TAX website ....
Working out and reporting the tax-free amount
The tax-free limit is:

Base amount + (service amount × years of service)

The base amount and service amount are indexed annually.

For example, for 2019–20 the tax-free limit is equal to $10,638 (base amount), plus $5,320 (service amount) multiplied by the years of service. Therefore, for 10 years' service, the tax-free limit for the year ending 30 June 2020 is:

$10,638 + ($5,320 × 10) = $10,638 + $53,200 = $63,838

The tax-free component of a genuine redundancy or early retirement scheme payment is shown at lump sum D on the employee's PAYG payment summary – individual non-business or Income statement.
""