Originally Posted by
YVR Cockroach
Even where I am there are astonishing 2 (wholly) Chinese language channels on and all the non-H.K. ones are in mandarin. Part of the reason is that Mandarin speakers now outnumber Cantonese speakers in the country. I see that in Chinese-operated shops where I (and others) have to communicate in English where previously, Cantonese was used.
As you probably know, one of the many Chinese words for Mandarin is 普通话, which = common language. I think this term was coined during the 1950s around the same time simplified Chinese characters were introduced in Mainland China. Both of these measures were designed to facilitate communication between people from different regions, and also improve the literacy rate (i.e. simple characters might not be pretty, but they are easy to learn).
Switching topics to the US/Canada, when I was a kid, differences in regional accents were much more pronounced than they are these days.