For context, I'm in Singapore, and I suspect the vast majority of these spam calls are manned by PRC people.
Try some Nihao’s and then say you’ll go get grandma or something. You’re just the child answering the phone for your immigrant parents that always forget that the call is on hold.
Funnily enough, I am an immigrant parent myself here.
† - I have on idea which language specifically was being spoken. Probably Mandarin, but how would I know?
Most of them are from "immigration department" (incorrect terminology for the UK BTW) and are about invalid visas or the like. Some claim to be from the Chinese Embassy.
I mess with them on the personal line but never the work. (Ok, that’s slightly different than answering vs not).
Informally, I don’t see a difference and this is after years of this hilarious activity.