Things which are inherent in being human can cause problems.
They aren't going away.
But it's illogical to say that means they aren't problems.
Well, you said it, not me.
Rape is a problem that is also not going to go away. But that does not mean that it's wise for us to simply accept it as inevitable and participate in it to the degree that it helps us 'succeed' in life. Yet this seems to be your attitude toward greed and selfishness and the endless damage it does to human culture and society, and to millions of individual human lives.
To recognize the traits humans have doesn't mean that one must commit wrongs in order to "win".
It does when traits like greed and selfishness are perceived by a society and it's culture as virtuous, and it's systems of interaction reflect that, as they CLEARLY do in our culture and society, even by your own admission. When the systems are rigged to advantage the greedy and the selfish the individual is basically forced to become greedy and selfish just to survive in it. Again, as you have already admitted, yourself.
Pragmatism is about achieving the best possible result.
The best possible result for whom? There's that selfishness, again.
An idealist who imagines humans to be better than they really are shouldn't design systems for those humans.
How sad. How will humans ever become better than they are without aspiring to do so, and without designing systems for themselves that help them enable that goal, instead of enabling our lesser, self-destructive characteristics?
Why do you think we have laws against rape and murder if pursuing that ideal is such a hopeless waste of time?