I think this sounds like a stupid question but I think my perspective is blunted because of the sheer info I've read on it already.
For example, the CIA produced hundreds of radio stations, magazine publications and propaganda leaflets denouncing leftist groups in 1970s Chile. Did any ordinary Chileans question this sudden uptick in anticommunist propaganda in their daily life? Did they know the CIA specifically was behind them? Same applies to Argentina, Nicaragua, etc.
Additionally, were ordinary Americans generally aware of their country's role in the abuses of authoritarian Latin American regimes during those times? Or were the Archives of Terror and the declassification of Operation Condor documents in 1999 a genuine shock to the American public?
I have previously found answers by /u/ainrialai and /u/aquatermain and /u/colloquialanachron for Why did the US overthrow so many democratically elected governments in Latin America? And why did they replace those governments with fascist dictatorships instead of liberal democracies? that will be helpful to you.