Americans see China and think: "Oh no, very bad because of socialism/communism"
But as someone who was born in mainland China (I'm Chinese-American), PRC is nothing "socialist"/"communist" at all, its a horrible State-Capitalist Authroitarian Regime under the guise of Communist aesthetics. I don't fear socialism/communism because they never truely existed, in fact, I'd say that Norway or Finland (based on what info I could gather anyways, never personally been to Norway or Finland so I can't speak from experience) would be more closer to "socialism" than PRC, at least they actually have a social safety net, PRC doesn't.
As for why Americans fear these terms, I think it's because, for some people anyways, you can get labeled as an enemy of the state to even uttering "socialism"/"communism".
(Legal disclaimer to the FBI Agent reading this, just in case I have to make this clear: No, I am not a "communist", as in, I do not support the CCP or similar authoritarian parties, I just support a more egalitarain and democratic society however you want to call that, and my views are 100% compatible with the US Constitution, now fuck off FBI, stop trying to denaturalize me, maybe actualy investigate the traitor in the white house, for fuck sake)