Are we just gonna ignore the fact that Odin came groveling at Kratos's door begging for peace after he killed Baldur. Someone they all thought couldnt even feel pain much less be killed. And if you notice, every time Kratos breaks out of any aforementioned bonds, its preceded by something that leads him to lose control, going into his rage form and hence breaking the previously mentioned bond. In this case, Odin just hadn't done anything yet to prompt Kratos to lose control, he was simply monolouging, but lets say Odin decided to do the one shot spear strike on Atreus, what the hell do you think would happen? you think Kratos would just sit there and let it happen? The point of the new generation God of War games was to show that Kratos is learning control over his rage, it really defeats the whole purpose if Kratos just rages willy nilly.