No Willis....what he is suggesting is that God predetermines everything.....the Absoluters position...we are all puppets kinda nonsense. Thats so akin to fatalism it isn't funny.
No they're not, because they cannot possibly do otherwise, it is impossible in your view. They can't even desire to do differently, they are cursed with a depraved nature.
And you yourself said only God can change a man's nature, didn't you?? Adam didn't give himself a depraved nature, he did not have this ability. It was God who cursed Adam and his posterity to have a depraved nature in your view.
Man can only be accountable if he has the option and ability to do otherwise. If we are born with a nature that cannot possibly even desire to obey God, how can we be accountable for that? You didn't choose to have this nature, and you did not give Adam permission to be your representative.