I can't find Supersnoop's post to reply to so I sort of having to hitchhike on yours.
I think he's in danger of overgeneralizing Overseas Chinese by his reference to "pro-democracy" supporters of overseas local-born Chinese millennials.
The ethnic Chinese in South East Asia have a long history of immigration to the region stretching back to 600 years (The time of Zheng He voyages) and still retain their Chinese culture and language. I believe this is also true to some extent in some western countries although to a lesser degree in terms of population. As opposed to most western countries, there is very little recent immigration from China to SE Asia in the modern era.
Perhaps a line should be drawn on the supporters on both sides (in Vancouver, I haven't heard of any demonstration in relation to HK in Asian countries) between those who immigrated from HK for political reasons in the first place and those who immigrated from China and HK for reasons other than political.
Just a slight correction: the earlier Chinese immigrants to Southeast Asia (not just the Treasure Voyages, see Wang Dayuan's Yuan dynasty journal Daoyi Zhilue about Chinese in Singapore and Indonesia in 1300), the Peranakans in SG/My/Indo, and the Thai Chinese+Philippine Sangleys lost their Chinese language long before colonial rule, and their culture (clothing, family customs) heavily infused with native practices. Peranakans did retain Chinese identity: many of them actively participated in the Xinhai Revolution but again, desire to Westernise China prob had something to do with it
Virtually none of the Singapore Chinese migrated because of political reasons (it was all about looking for work), but the same anti-China attitude can also be found here. The simple reason is that the British set up a hierarchy of job and business opportunities in their colonies with them on top and the Anglicised subjects next in line, with those who couldn't speak English at the bottom. When the British left, the 2nd class (people like Lee Kuan Yew) took over, perpetuated the hierarchy, restricting recognition and assistance to Chinese-medium schools while opening the economy mainly to Western MNCs and expatriates (and China was busy with GLF and CR at the time, and made culturally-Chinese people look ridiculous). This led to the infamous Pinkerton Syndrome where all things Western automatically became 'modern' and superior. The Chinese in SG and HK were willing to bear with 2nd class status because in their minds they were not really at the bottom, the "Ah Tiongs" (mainlanders) were the worst. That's also why they are now in denial about the fact that China has overtaken Singapore, Hong Kong and most of the West in technology, infrastructure, law and order and prosperity, because admitting it would destroy their ego. Few care about democracy, SG isn't one either. those who do are also motivated by blind idolising of all things Western, again to make themselves feel 'progressive', 'advanced' and 'modern' i.e. superior. of course American multimedia aids this, but they only believe because they have a confirmation bias, and they won't believe anything from China. so the suggestions to expand Chinese media global presence, yeah, not going to work...
The HK riots are almost entirely an identity issue. the housing/cost of living problem has been there since the Brits but nobody did anything like this.
When I was in ml China I noticed the decor/design/arts almost everywhere (esp. high end places) were Western (SG and HK is the same); non-Western more to be found at ancient sites, or low end places (else cheap quality or obviously inauthentic) so people don't psychologically link "Chineseness" with modernity, prosperity etc. The Japanese and Koreans infuse everything with their pre-Westernised culture: in SG many hold these in higher regard. the British propagated their culture and thence influence that way too. whatever your views on "changing culture" or whatever, stereotypes are a powerful psychological tool. The only way to undo the damage is a reversal of the hierarchy of opportunity with all forms of Chinese identity expression at the top.