I think people fall back on quantum mechanics too readily when talking about consciousness and free will, just because it's mysterious and random. I'm not sure anyone has provided any evidence that quantum mechanical effects manifest meaningfully at the scales needed to drive thinking, but I'd be very interested in reading about it if they have.
The other side of it too is that even if decisions are influenced by quantum mechanics, it's still random. Probabilistic is still random, just with some constraints - there's still no you making the decisions at that point, unless souls are somehow quantum mechanical in nature and drive hidden variables we can't observe. That's not impossible, but it's also unfalsifiable so it'll never leave the realm of philosophy. On topic here I guess.
I like to think of it this way: either we make our decisions entirely based off of our past experiences and current situation, or there has to be randomness involved. What alternative is there? If you make a decision that isn't based on previous experience and your current observations, then that implies the decision was influenced by something not even based in reality.
On the topic of punishing people even when their behavior is deterministic, I don't think that's necessarily illogical. People still learn from punishment and it influences their future behavior. I think it should guide the way we punish or rehabilitate people though.