While China opened access to Wikipedia, it's still blocking some topics selectively:

In removing restrictions on Wikipedia, the Chinese government appears to be choosing to rely instead on keyword filters that block specific material on all sites, including Wikipedia. Subjects that are still off-limits on Wikipedia include high-level politics, the suppression of the pro-democracy movement in Tiananmen Square in 1989, the Falun Gong movement and historical events like the Communist revolution.