Are you aware that a big majority of Chinese who visit the US or cross the firewall immediately become little Maos lolI hope what you said is true overall. But based on my observations, I saw intense anti-China sentiment among some young Chinese who have money and education to cross the firewall. In the past, these same people supported CCP and defended China against western attacks in western social media like twitter and reddit. Now the same Chinese speakers are either gone and replaced by intense China haters or they have themselves changed their minds.
There used to be alot of pro-China and pro-CCP opinions on Chinese speaking reddit subs and twitter accounts. Now its overwhelmingly negative. i notice intense hate for China in these places, its like they would rather see China split into different countries just placate to the west and attain "peace" and "democracy". This change happened in just 1 year.
As for why Reddit/Twitter is overtly negative, have you considered that maybe their master has ordered them to purge pro-Chinese views.