What are you trying to do? All of the things you listed are important, and shouldn't be removed by default. If you press enter on the "–", you can collapse the thread, and that's super useful for screen readers for threads that are not interesting and we don't want to read. Also, the username is a link, and I almost always click it before replying to a post or comment, to see if the user is a troll, or if they're honest and I should bother trying to have a conversation with them.