The question isn't whether or not you are hackable, it is whether or not you want to go along with the hacking effort.
For someone with a great deal of experience and perspective on the world, it is difficult to break their will. For someone whose view is naive or very narrow, how do they find the will to oppose an effort when that vision has been shattered?
Take, for example, the hypersexual behavior common among abused women. There are various patterns of logic they may embrace as an alternative justification, but they all avoid the reality - that they would have grown up to want a stable partnering capable of having children had they not suffered the abuse - and the abuse did not change this desire, it simply shattered the vision of how that partnering would go.
They may claim they like the lifestyle that they live or that it is their choice - but they lack the perspective to understand that a harder orgasm brought about by adrenaline is a simple substitution of hedonism for fulfillment. Like a drug addict, they seek the momentary pleasure to escape the pain of the reality they will not recognize and our culture holds up as an example of how different lifestyles can be valid and rewarding.
Programming humans is more difficult, but can also be done within the same context of shifting their will to be aligned with the programming.
This also depends on what we are calling a "hack" - as there are a number of things that can involuntarily place you into states of higher blood pressure or stress.
You are correct if you mean that there isn't a way to make a video that people will see once and start clucking like a chicken when they see a penis or something.