[gertlex]

It is unsurprising that it varies by country, etc. Below is pure speculation while eating a snack:

Likely dishwashers for the NZ market are designed to actually spend sufficient time heating the water.

My impression from watching the TC videos a while ago is that at least in the US, (many) dishwashers probably only do a insufficient time interval of adding more heat to the water.

It makes sense that different markets developed different ways; the brands that optimize for the local trends (cold vs hot water) can skimp on some features and have lower costs.