I think comments tend to attract certain people. The vast majority of people don't say anything so you are left with the squeaky wheels. But because when you read it it feels like a overwhelming amount of people that are seemingly very ignorant it does feel quite disheartening. I've personally limited my exposure to comment sections of most news these days.

The problem with reasonable people withdrawing from the most popular online forums is that you end up with a vicious circle of the most unreasonable people arguing with each other and influencing public opinion.

Add a real name policy to the mix and you will only retain the absolute elite of squeaky wheels.