I suppose, fundamentally, it boils down to human nature. I have said for many years that to ever have peace in the world you would have to dehumanise people because we are an overbearing and particularly violent species by nature. We are still animals, just far more advanced than any others on the planet, and we are fallible. Perhaps it is by design, or perhaps it persists because it is a natural necessity?
If we all lived in peace and nobody ever did anything 'wrong' what benchmark would be have to judge our own morality? If we were all equal, what incentive would there be to develop and achieve? If we all agreed on the same thing what reason would we ever have to question or challenge? This fundamental conflict is what creates change and to a large degree is the catalyst for progress. Without it we would become immobile and stagnate.
To fix the problem you would have to remove our nature, remove our emotions and make us operate like robots for the greater good. In nature the world tends to turn based on equals and opposites but most importantly balance. You can't have love without it's opposite existing and whilst it exists, it is a tool that can be used for harm. But if it didn't exist how would we properly appreciate Love? It is like hot and cold. How can you fully appreciate a roaring fire if you have never been cold, or a cooling breeze if you have never been warm? That contrast is essential in our comprehension of our surroundings and in maintaining our moral and ethical compass.
What we see here in this thread and on the forum in general is that same phenomenon in a microcosm.
So to conclude, humans gonna human!