Everyone has a choice. They choose their actions, they choose who to listen to, they choose what to believe. They choose to be open or closed minded. They choose to listen to new ideas or not.
A lot of people are choosing wrong and suffering for it. They had a choice. No one can take that away from them, they always had a choice.
Propaganda only works if you choose to believe it.
For you and me it might be, because we may have the acquired skills to research sources, spot bullshit, etc. We still miss stuff.
But for a lot of people "choosing wrong", it might just be the sum of their environment. A media diet too heavily reliant on Facebook for example.
Ah but they're choosing to stay on Facebook you say... Well, yes, but if they can't directly make the link between Facebook and the propaganda, they don't even know they have a choice to make.
"Free will exists" is a hand wavy way of victim blaming here, imo. There is a reason these people are called victims of propaganda, not willful soldiers.
For what it's worth, I don't disagree with you entirely. However I don't think it's as simple as being helpless victims of propaganda or other deceitful information.
Everyone has the choice to ask, "but what if they're wrong?" That simple question alone illuminates the incremental path to greater understanding (however long the journey may be). Many of these people who have been enthralled by the narrative that vaccines are dangerous and unnecessary are otherwise normal people. They're able to function in their jobs and day to day life. If they believed everything anyone told them they'd never be able to function in society, and yet they do function. Precisely because they are able to choose who and what to believe; we all do it every day! They choose to never question certain sources or authorities. It's a willful choice.
A lot of people are choosing wrong and suffering for it. They had a choice. No one can take that away from them, they always had a choice.
Propaganda only works if you choose to believe it.