At the risk of sounding dismissive... Who cares? Whether free will is an illusion or not has no practical application to my life, my behavior, or the lives and

At the risk of sounding dismissive... Who cares? Whether free will is an illusion or not has no practical application to my life, my behavior, or the lives and behaviors of other people. If an illusion is so strikingly believable that you take it for reality, what separates it from BEING reality?