Frank's nod is respectful, he understands that perspective. For certain instances, he can even relate. But it isn't his kills that ever kept him up. It was the people left alive to fuck shit up for him. Which he supposes Reid also touched on. "Good choice." Better than dying at some scumbag's hand. He seems like a good kid, someone who really cares about other people. Frank's never fully been formed that way though, even if he can recognize it easily in others.

"I didn't want to live through it. No one does, right? They all off themselves at the end." He shrugs a shoulder like it's nothing. But it's not nothing, not even to him. At the end, he had a change of heart. Frank Castle wanted to live. And maybe now, he wants to change.