>I don't mind when people post pictures of their avatars or photos that they've taken. Why do you?
Because its avatarfagging and its against the rules. Posting a picture of yourself with every posts defeats the purpose of an anonymous image board. You're basically namefagging but doing it a way that people can't filter you. 
>Why is the bar so high on what is "good enough" to post?
It's not. Talk about VR games instead of posting selfies like this is a teenage girls instagram page.