This one is interesting to me. I could certainly be accused of being this guy, you could probably make an argument that I'm being this guy right now.
We're all here and participating for different purposes, and one of my purposes is to sharpen my writing skills and my rhetoric. Arguing with strangers on the internet is the most effective way of doing this that I've found, that doesn't affect my personal/professional life.
Another thing you mentioned - people with immense issues. We've all got plenty of issues, and one of the best things about commenting anonymously on the internet is that there is no punishment for revealing them.
I think that there are positive perspectives you could take on some of these bullet points