It's interesting that as an American, I can't tell if you are talking about the Chinese or the "liberal elite Americans" when you state this. That's a common talking point of the American right wing and could equally describe the position of any person who uses that Chinese term in seriousness.
Also, the hypocrisy of a Chinese word criticizing westerners for enforcing political correctness is humorous.
Also not sure what this word has to do with FBI anti-intelligence efforts.
(Leaving aside question of whether the Chinese “Communist” regime is on the left in any substantive sense, rather than merely as a historical rhetorical affectation.)
China is State Capitalist, not Communist. The government doesn't tell people what jobs to do and provide them with their home, food, and consumer goods
(This is structurally similar to the right-wing capitalist criticism of welfare states, which is basically the same but substitutes an amorphousus government elite in place of the capitalist one.)
And to answer your question -- yes it's a real word, and is used on Internet a lot. Literally it means white ("bai") liberals ("zuo" -- left).
Even the Chinese have a word for these people who naively defend and turn a blind eye to this sort of thing: "Baizou".
From Wikipedia:
"The word baizuo is, according to political scientist Zhang Chenchen, a Chinese word that ridicules Western "liberal elites". He further defined the word "baizuo" with the definition "People who only care about topics such as immigration, minorities, LGBT and the environment" and “have no sense of real problems in the real world”; they are hypocritical humanitarians who advocate for peace and equality only to “satisfy their own feeling of moral superiority”; they are “obsessed with political correctness” to the extent that they “tolerate backwards Islamic values for the sake of multiculturalism”; they believe in the welfare state that “benefits only the idle and the free riders”; they are the “ignorant and arrogant westerners” who “pity the rest of the world and think they are saviours”.[7] The term has also been used to refer to perceived double standards of the Western media, such as the alleged bias on reporting about Islamist attacks in Xinjiang."
https://en.wikipedia.org/wiki/Baizuo