Instead, whether or not you need to pay GST in New Zealand is related to your taxable activity.
If you earn more than $60,000 per year, in Uber income alone, you will need to be registered for GST with IRD.
If you earn less than $60,000 per year in Uber income and also receive a salary or wages from another job, you will not need to be registered for GST. No matter how much you earn from your other job (provided that the income is already taxed), it is your Uber earnings that determine whether or not you need to be registered for GST.
If you earn less than $60,000 from Uber but have other untaxed income (Eg: you also have your own profitable business), it is the total amount of income determines if you need to be GST registered. For example, if you earn $30,000 a year through Uber and $40,000 through other untaxed income, you will need to be registered for GST.