This comes down to the difference in underlying values of different cultures. Forcing what you think people should want onto others when it's not what they really want isn't effective, even despite your relative moral justifications. There are ways to accomplish notifying the user of censorship which isn't shoving it in their face.

Users simply won't use Google if it's beating them with a stick to remind them that websites are censored and that users should use a VPN. Chinese citizens know about the censorship and most, outside of specific provinces, simply don't care. Those who do already use a VPN.

Showing search results that are based only on the websites themselves isn't "beating them with a stick to remind them that websites are censored".

This is one of a very few places where I don't mind projecting my cultural values, and in fact consider it morally unjust not to do so.

Another would be equal rights for women and ethnic minorities. I don't care if someone else's culture dictates that men should have legal control over their wives, or what have you—that's abhorrent, and human rights should be universal.

That's precisely how, throughout the history of mankind, one tribe of people have forced their viewpoint onto others - because they thought it was right.

The false equivocation of protecting minority groups and human rights with "Should we notify of censorship in the results or the bottom of the screen?" is telling in this regard.