Right. I don't think you need to drop down to the level of quantum physics and neurology for this - I feel that economics invalidates free will just fine on its own.

After all, the supposedly free-willed humans aren't behaving randomly - they're making choices they see as beneficial to themselves (or "good" under their system of values). Meanwhile, economics as a field is all about predicting what choices people make facing specific situations, in order to force people to make specific choices by engineering situations they face. At scale, it works spectacularly well, but even at an individual level, it's just a matter of tailoring manipulation.

One may counter: "I have free will, therefore I can choose not to follow the incentives" - but you are going to follow the incentives anyway, that's literally the definition of what they are. Kryptonite to free will. The thing that allows me to predict what the free-willed you will chose - with perfect accuracy in the theoretical limit. So what's the meaning of free will if people can be made to behave deterministically?

In fact, that's what society is about. That's what civilization is about. Making people behave deterministically to a good approximation. That is, making people predictable to each other. The people who, by their "free will", choose to not follow incentives? We label them as loonies and lock them in mental hospitals, as they're a danger to themselves and everyone around.

To sum up: I increasingly feel the question of free will is meaningless in practice, because having a society is fundamentally opposite to it.

I like to think it's a probability distribution that you have some influence over.

I choose to catch a ball. I've just made it 99% likely that I'll catch it. But there's still room for chaos to ensure it's not a deterministic outcome.

Free will is sometimes failing at things you set out to do? We hardly need quantum theory to explain that humans are clumsy or sometimes mispredict the trajectory of a thrown object.

Free will is deciding what to do under the known bodily/physics constraints. Free will is thinking and imaging whatever you want under no constraints.