The main point is the "downvote and karma" system. (It's not real karma in Buddhism)
Some people love to downvote others, some people don't. I notice only the most offensive and intolerance group of people love to keeping to click the downvote button. So they can be rude to any minority groups and thoughts on there.
Turn out Reddit is the wonderland of them.
The real Karma is, they become more and more stupid by lack of diversity.