[xii22]

On your Portal point, the reason for that is that sarcasm as humor is not really a 'thing' in Japan, in general terms. Some people go as far as saying that the Japanese do not understand sarcasm, but that's an exaggeration

[fiblye]

Yeah, it’s generally just regarded as mean.

On the contrary, I’ve found it’s something that most other Asian countries get really well, so the difficulty seems to mostly be limited to Japan.