I think the writers classification of this being a Chinese vs English distinction is a bit presumptuous - the portion of the USA OP is familiar with maybe, but I'll jump on the bandwagon to say this kind of negated negative language is very very common in New Zealand.
Not bad, not wrong, no problem etc etc are all very common, and we have the following too:
Nah yeah = yes
Yeah nah = no
Yeah nah yeah = yes
Nah yeah nah = no
...extend outward to your hearts desire
(yes people commonly say all of the above)