I live in New Zealand - until 2019 things used to work this way for us too. A law was introduced to require overseas sellers selling more than $60,000 NZD/year into New Zealand to collect pay our Goods and Services Tax.
Now Amazon/Temu/AliExpress others all collect 15% NZ GST at the checkout. It's pretty seamless as a buyer, just that GST is not usually shown until checkout unlike domestic sites.
https://www.ird.govt.nz/gst/gst-for-overseas-businesses/gst-...