Alcohol.
Lots and lots of people lean heavily on it and think that alcohol is the spice of their life. When, it contributes to so many problems than it’s so-called benefits. We tried, in America anyways, to outright ban alcohol. Problem was that the person who wanted it banned, was too extremist.
Like he didn’t think it all through and think just going for the jugular of the problem is what will work. When, it didn’t and just made people work around it until eventually the ban was dismantled.
So, since then, we’ve been putting up with drunk drivers, drunk disputes, drunk abusers and other issues. I still wish we could just slam our hands down at the desk and demand we sit to discuss in how to properly deal with this issue than people proclaiming that it’s not a problem.
It definitely is a big part of our nature as social creatures.
Although we can cooperate with our group and fight against another, hence the consistent wars throughout history.
I think human nature isn’t one sided.
But you’re right in that cooperation is the most effective (and desirable) way of survival.