I can see where your reasoning is coming from but I mostly disagree. I can see two factors that could prevent manipulation: 1. The rare case of wisdom (that I define as being strong willed enough to think independently and not fall for self-deception/wishful thinking + intelligent enough to think correctly) which doesn't apply here since education doesn't influence this and 2. Manipulation going too much against the previous indoctrination, which does apply here but kinda defeats the point.
In fact, I'm mostly distrustful of intellectuals (!= intelligent people). That misattributed Thucydides quote about scholars ("The society that separates its scholars from its warriors will have its thinking done by cowards and its fighting done by fools.") further illustrated by Uncle Ted ("Though they like to fancy themselves independent thinkers, the intellectuals are (allowing for individual exceptions) the most oversocialized, the most conformist, the tamest and most domesticated, the most pampered, dependent, and spineless group in America today.") summarize my position.
Where I do agree is that practical/technical knowledge allowing individuals to be more independent and less reliant on specialized technicians to change a light bulb is highly important. Sadly, the Western world I (we?) belong to has almost finished removing teaching of DIY and even the individual ability to do so (cf modern cars, appliances or operating systems). I suspect that this isn't a coincidence considering the aforementioned ramifications...