It's possible English isn't your first language? No worries.

The word "vindicated" doesn't mean "won in the end," it means "they were right." As in, justified in their demands, on the right side of history. Even of the protests I listed in my first comment, half of them didn't actually win in the end (Vietnam, Occupy, Gaza, and arguably more).

From Wikipedia:

...(the Seven Demands) for the government:

1. Affirm Hu Yaobang's views on democracy and freedom as correct.
2. Admit that the campaigns against spiritual pollution and bourgeois liberalisation had been wrong.
3. Publish information on the income of state leaders and their family members.
4. Allow privately run newspapers and stop press censorship.
5. Increase funding for education and raise intellectuals' pay.
6. End restrictions on demonstrations in Beijing.
7. Provide objective coverage of students in official media.[84][83]

I hope that you'd agree that the students were in the right, and that the oppressive CCP was in the wrong?

They are winning.* It's not over yet.

wasn't the Red Guard also a student movement? it didn't get deleted, but it's definitely not looked back upon fondly. tbf most of what I know of it comes from Three Body Problem though, so I could be wrong.

there's also the Red Army Faction (Baader-Meinhoff gang) in Germany during the '70s which killed some people.

Never knew until I immigrated to the US. And even then, its merely a brief mention on it and calls it “communism” (its not lol) and then the teachers proclaim its why “communism” is bad, USA constitution rule of law blah blah.

That's when you bring up Kent State

If they won they wouldn't still be trying to exert power. It's not over until they stop.