Tian'anmen square is a famous historic site, not an event. If you mean the June 4th incident, Operation Yellowbird is documented on Wikipedia itself and affirms CIA involvement. Looking at prolewiki, the page on the 1989 Tian'anmen Square riots has 33 sources listed, with sources ranging from western outlets like BBC and CBS, to scholarly sources, to wikileaks. The analysis that this was a counter-revolution, and therefore the socialists were correct in putting a stop to it rather than letting it overturn socialism, is based on the information that I believe to be well-rounded and well-sourced.

Do you disagree with the sources, or with the Marxist analysis provided based on the sources? If it's the former, what sources should be added? If it's the latter, then that brings us to back to my claim that the bias is better to be open and honest, rather than hidden, and that the basic facts are still solid and real.

"I mean it straight up asserts something that contradicts what the authority figures in my life told me as a child, so obviously that means it's wrong"

-You talking about Prolewiki or any Mormon talking about a biology textbook

Which it was. Do you not look into things before talking about them? You also say it "asserts" it, as if it doesn't source the claims made.
You seem to be conflating "not reinforcing my worldview" with "being wrong and unfounded"

They claim anything bad China does is a CIA plot, fuck sources.