>>99239745>>99239886He held back against Boros because he empathized with Boros' ennui from being too strong. Basically, he wanted to give the guy a "good fight" and know the satisfaction that eludes him.
With Garou, he was never fighting to kill to begin with because he could sense that Garou was just a "human playing at being a monster"; he doesn't use lethal force against humans. On top of that, he could tell that Garou was "close" to making a breakthrough, but unfortunately hitting the wall that is Saitama caused him to give into despair instead of breaking past his limits.
Saitama is probably insightful enough to recognize that Hulk is a human being, even if he wasn't aware of Bruce Banner. That being the case, he'd go comparatively soft on him. However, I'm not sure how far Saitama would be willing to let things go before just knocking him out (and overwhelming force has been enough to just flat out knock Hulk unconscious before), especially if civilians started getting injured.
