>>280841181
This. Besides justicefaggots like Kiritsugu always end up miserable and alone. It was already proven in Fate/Zero how Kiritsugu's ideal was childish and unattainable and Shirou trying to follow it would only lead to despair.
That's why HF is the adult route, where Shirou understands and lets go of childish ideals to form a family with Sakura and protect the city, granting justice within his limitations and living a happy life doing so.