It's interesting and sad to see the forced assimilative process of erasing written Cantonese. I remember HK in the late 90s still had newspapers that published

It's interesting and sad to see the forced assimilative process of erasing written Cantonese. I remember HK in the late 90s still had newspapers that published in written Cantonese. Just across the border in Shenzhen, without the British influence and prior to the explosion of industry and tech in the early 2000s, you could still see nonstandard signage that were in Cantonese in store windows. I think getting rid of spoken Cantonese is likely a generational and not just an effort that can be done in a decade or so, but I've both experienced and did field work on how the Wu dialects were more or less systematically erased from official, and now even private realms. The Shanghai variety, itself developed only in the early 1800s from a pidgin of the Suzhou and Nanjing varieties mixed with northern influences, is actually quite well-documented by foreign sources in writing, with a pidgin developing off of that and English and Portuguese that also survives in English sources and academically studied in great detail by Chinese authors in English but not in Chinese to anything close to the same degree. Starting with the millenial generation the speaking of the dialects in schools, even outside of class, became subject to punishment. With public education starting at the pre-kindergarten level enforcing the rule, across two or three generations even those whose first language is one of the dialects became more or less forced into Mandarin speakers and losing their fluency. I have little reason to doubt that something similar will simply be forced upon Hong Kong as well. Luckily sci-hub is your friend and written Cantonese seems to be better represented than written Wu through a cursory search.