Online culture and censorship have broken the ties that once spurred protesters.

Today, June 4, marks the 36th anniversary of the Tiananmen Square massacre—a moment of both tragedy and hope. It was the bloody end to a nationwide democracy movement that brought together workers and students, the most promising push for political reform in the history of the People’s Republic of China. But despite the courage of many individual Chinese who fought for democracy and the solidarity of their international supporters, there has not been a comparable movement since—and it’s hard to imagine one arising anytime soon.

It wasn't paywalled on my phone, but apparently it is when viewed elsewhere.

One of the key factors mentioned in the article: the erosion of the "the middle ring" from many societies (not just China): "close-ish" but not intimate/familial face-to-face relationships (neighbours, coworkers etc.) that are key to growing a social movement with real world activity.