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.
"those people are awful psychos and we're better than them" is reductive and ineffective at explaining both why they're doing what they're doing, and why it's bad. It's also, crucially, the exact language they would use to explain why it's right and good for them to exterminate the population of Gaza. Posting about how much better you are doesn't improve material conditions for anyone in Gaza, but it might make you feel better about (forgive me for making statistically likely demographic assumptions) living in a white supremacist settler colony benefiting from generations of human slavery and the genocide of an indigenous population.
If you believe a person is bad because they do bad things, then the person can change with the action. A person can stop doing bad things, and thus stop being a bad person. If you believe a person does bad things because they're bad, then the only solution is to kill them.
I believe that the genocide in Gaza is bad, and the solution is to stop the killings and allow the people of Palestine to return to their homes. I don't believe the solution is to exterminate the "bad people" until only the "good people" are left alive, which is basically how the Zionist occupation government would describe its official policy toward Palestine at this point.