These files have been available for at least a few years and despite their availability, very few users have actually been able to successfully print and shoot a 3DP gun. To be specific, these files allow users to print the receivers for guns, not a ready-to-fire weapon. They still require further resources to be used as weapons. Here is a great explanation of what those files actually enable.
The machines needed to print these gun designs are prohibitively expensive, thus it’s still much cheaper to purchase an actual gun at a pawn shop or some other reseller. For reference, one manufacturer of machines that can handle these files, MarkForged, has a starting price point of $3500+.