I wish there was an archive of r/askhistorians. It looks like they nuke discussion after they get one decent sized answer. I cant seem to find older threads too.
They continuously nuke answers and comments which does not conform to their standards, regardless of whether there is a legitimate answer or not. This is why so many threads appear empty, with only "[deleted]" answers.
The closest thing to an archive are the weekly "Sunday Digest" posts, in which people nominate their favorite answers of the week. It's eclectic and scattershot when it comes to topic, but the answers themselves are often interesting and well constructed.