Before epilepsy was understood to be a neurological condition, people believed it was caused by the moon, or by phlegm in the brain. They condemned seizures as evidence of witchcraft or demonic possession, and killed or castrated sufferers to prevent them from passing tainted blood to a new generation.
While our lives are largely dictated by situation and environment, this doesn’t equate to a complete lack of free will. We are constantly making decisions based on reacting to information we receive.
Even if we don’t actually have free will, it’s not really a useful argument to make. It just feels like an excuse to dismiss the problems of humanity and ignore opportunities to learn and change.