Look up 80% lowers if you want your world rocked. The fact is that the tech to homemake guns has existed. Technically you’re supposed to stamp an identifying number and register them with your state DOJ, but are the people who want to make a non-serialized gun really going to do that?
I could make an AR lower with my drill press (as a shitty substitute mill), but have no desire to.
This technological cat is out of the bag so long that it’s already had a few generations of feral kittens…