Propaganda doesn’t totally rob people of agency free will (more accurate term), if it did this site wouldn’t exist. People do have the capacity to develop critical thinking, skepticism, and a basic curiosity about the world that allow them to develop some resistance to propaganda.
You can hold people accountable for failing to even attempt to do this.
I believe people who study Marxism-Leninism seriously tend to have a more accurate understanding of politics and propaganda than the average liberal because history has demonstrated Marxism-Leninism’s explanatory power in describing the relationship between past conditions and current conditions to accurately predict future conditions. That’s very different than the OP’s suggestion that humans have an innate hierarchy of value that expresses itself in the form of better people espousing better ideas, which is the same self-justifying vanity that led colonial powers throughout history to make the same claim to justify stealing land from “barbarous” natives who demonstrated their inferiority through their “failure to develop civilization”.
I really don’t think that’s the concept the OP is invoking-- consider the choice of the word develop rather than something like innately possess
I don’t disagree with your criticism of the concept itself, that sort of exceptionalism as well as the view of oneself as a static, immutable essence (or defined by static, immutable characteristics) are both dangerous