What's funny about determinism is the notion of "before and after" inside a localized time-space. We all know (I'm assuming) that if you're going far back enough to the beginning of the universe it's not quite the steady picture determinists put faith in....and whatever you may consider the end of the universe to be (heat death/big snap) at some point, whatever you imagine of cause and effect, won't be anymore either.
At best, in their tiny lives, in their tiny spaces, they look at the world as if it's all mathematical precision....as if they can't understand that math is entirely incomplete, and filled with paradoxes.
What they call cause and effect may be nothing more than their tiny minds, tiny perceptions, trying to describe a localized time space they cannot possibly comprehend on any macro-scale. Sure guy, it's all cause and effect and you can neatly place now after then and before afterwards. That's a super-duper way to describe everything....not merely the limits of perception or comprehension lining things up for you in an easy-to-use manner.
But yeah...free will describes human behaviors much better than determinism no matter how many arguments you'll make and you will 100% default to acting as if it's real, all the time, just like everyone you look down your nose at.
But no...there's no extremely clear or even obvious value to the idea that because things appear to operate the way they do now, they always will. It's not even a logical conclusion.