"Sure." What else can he possibly say to that? He wanted to believe that he was doing everything he could, but in the end, it was not a desire to save or protect that left Stormbreaker lodged in Thanos' chest. It was a real desire to see Thanos suffer, to make sure he knew exactly who it was who killed him.

That wasn't everything he could.

He gives Tony's hand a tight squeeze, then lets it go.