Effective and fun are two different things. Clearly, he thinks it is not fun to sit on to of the building and hide. Regardless of whether or not it is effective, if you don't enjoy it, don't do it. It is also effective to turn off blood moon, but if you like blood moon, turning it off makes no sense.
People choose optimal? They can, yes. But more often, in a game, people choose what is fun for them. I doubt you will find many players who hide on top of a building even if it works. Why bother having blood moon on if you are going to do that. Those who don't enjoy blood moon will just turn it off. Those who do enjoy it aren't going to hide all night. They are going to fight. How they fight and where they fight is entirely up to them, but they aren't going to hide. You will also find that many players enjoy a challenge and so increase the difficulty. They definitely aren't going to hide. And the hardcore players and min/max players (those who are going to play as optimally as possible) also aren't going to hide. You are wrong to think they will.
Ask yourself if you enjoy hiding on a roof even if it is safe. Do you enjoy being safe or do you enjoy fighting? If you enjoy fighting, would you prefer to hide and be safe, or would you rather fight? You seem to be saying that you would rather fight. So do so. You don't have to hide, even if it is safe, if you enjoy fighting instead. The game doesn't have to force you to fight. You can choose to do so, just like pretty much everyone who plays with blood moon turned on.