I'm no expert, but the DD AR looks factory unless it has a color matched 80% lower and those are aero lowers, right? I also havent looked into 80% shotty builds. Anyway, point is that somebody that isnt allowed to buy guns, has them.
Easy accessibility to CNC mills, 3D printers, drill presses, and easy-to-do 80% lowers/frames will continue to make fun of any and all gun control laws until all such laws are wiped off the books. Open source, freely shared information is impossible to "ban" on the internet.
Cant buy a gun from a store? Darn. Let me just order it on the internet for a few bucks more.