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.
The problem with change more broadly is that in order for someone to change, they have to WANT to change. I think a lot of people don't want to change. Change is scary. Change is hard. Change can end up being worse for the individual overall, it carries some risk. Many of us live in a society that largely pushes the idea that change and growth is bad, which is honestly the most insidious propaganda of them all. Folks have to take that first giant leap first and be willing to and open to change. Or they have to be forced into change via an upsetting of their material conditions.
it's not enough to want to change, you need to be able to as well. for one example, someone with severe adhd and no access to (effective) therapy or medication isn't going to change shit, not matter how much they want to.
kill the protestant in your head.