So you just gonna ignore the countless atrocities committed by humans in the past such as human sacrifice, mass rape, and cannibalism?

You don't even have to go back a thousand years ago.

For example, US slavery didn't end until 1865. That's really not that long ago.

African American babies were used as alligator bait near the early 1900s

The Nanjing Massacre - 1937

The International Military Tribunal for the Far East estimated that 20,000 women, including some children and the elderly, were raped during the occupation.[57] A large number of rapes were done systematically by the Japanese soldiers as they went from door to door, searching for girls, with many women being captured and gang-raped.[58] The women were often killed immediately after being raped, often through explicit mutilation[59] or by penetrating vaginas with bayonets, long sticks of bamboo, or other objects.

The Nazi's were conducting human experiments and committing genocide in mid 1900s, less than a life-time ago.

Excerpt from wikipedia:

Experiments on twin children in concentration camps were created to show the superiority of heredity over environment, and to find ways to increase German reproduction rates. The central leader of the experiments was Josef Mengele, who from 1943 to 1944 performed experiments on nearly 1,500 sets of imprisoned twins at Auschwitz. About 200 people survived these studies.[7] The twins were arranged by age and sex and kept in barracks between experiments, which ranged from amputations, infecting them with various diseases and injecting dyes into their eyes to change their color. He also attempted to create conjoined twins by sewing twins together, causing gangrene and eventually, death.[8][9] Often, one twin would be forced to undergo experimentation, while the other was kept as a control. If the experimentation reached the point of death, the second twin would be brought in to be killed at the same time. Doctors would then look at the effects of experimentation and compare both bodies.[10]

The Rwandan Genocide that killed at least 200,000 people. Took place in 1994.

I could add hundreds, if not thousands more to this list, but this was only to prove a point. Humans are some fucked creatures, and by the looks of things, it's only gonna get worse as we technologically develop.