I'm not sure you're familiar with AskHistorians' purpose as a subreddit. It's not a subreddit for any old idiot to post any old crap, it's for historians to answer questions posed by users. Answers in the subreddit are expected to be in-depth and comprehensive, and to demonstrate a familiarity with the current, academic understanding of the topic at hand. If it's not that, it gets deleted so as not to crowd out what people are actually there to look at. There are also lots of good comments exploring answers to the question, because apparently you didn't scroll down.