At the very least, free will is a useful illusion, leading us to be more prosocial and ethical. Because even if we are just “a vast assembly of nerve cells and their associated molecules,” we’re a vast assembly that feels like so much more. William James, as usual, said it best: “My first act of free will shall be to believe in free will.”
The quoted blog post links to three studies on free will that is very interesting and you would do well to read (at least the original blog post and if that wasn’t enough for you the linked studies.) I generally believe in living rationally and the importance of truth in everything, but if for some people the truth is a little too hard, maybe for some delusion would be okay!!!!