The worry about this being a new avenue for "ghost-guns" is absurd. All you need for a gun is some metal pipe from a hardware store. These "downloadable guns" would be about as effective. Plus it's perfectly legal to make your own firearm from readily available parts. And it's not like the fed tracks guns anyway, so what's new?
The debate on this issue seems to be centered around the fact that these plans are downloadable online, which I think is silly since Google happily provides you with most of what you need already:
The debate on this issue seems to be centered around the fact that these plans are downloadable online, which I think is silly since Google happily provides you with most of what you need already:
https://patents.google.com/patent/US984519A
https://patents.google.com/patent/US6279258
https://patents.google.com/patent/US4539889A
https://patents.google.com/patent/US5827992A