"Don't be sorry," Strange explains, with a shake of his head. "None of this is your fault."

Even if Yuya could do something, what would he do? He couldn't have made it so that Strange's mirrors magically vanished or what have you. He can't fix Strange's arm. Strange appreciates the sympathy, but practicality is pointing out some flaws.

"Good luck," he simply says, giving Yuya a reassuring little smile.