This subreddit is heavily moderated. This is so that the answers people do see are accurate, informative, and thorough. For this reason, a lot of answers that are shallow, misinformed, jokes, or just links elsewhere are removed. The mods know that some people would prefer to see all comments, but there are other history-themed subs where comments aren't so heavily controlled. This sub has the premise that no answer is better than a bad answer, because a bad answer detracts from the visibility of a newer, better answer and also discourages people from posting better answers, because they'll end up lower on the page and getting less karma, and some people rarely scroll past the first answer. If you see a question that you like that doesn't have an answer yet, upvote it and come back later. :)

You can read more about the rules for the sub here: https://www.reddit.com/r/AskHistorians/wiki/rules