We're not up to our ears in homebrew nukes because making them is expensive, and that doesn't change. People have been able to make zipguns for over a century with nothing more than a few bits of pipe and fittings.
It's queer that merely the idea of knowing how to do something should be so distressing to policymakers.
AFAIK (without enough searching to land on a no-fly/watch list), those instructions are at a very high level and are not enough to produce a working bomb without further extensive research/experimentation. That at least accounts for some of the 'expensive' part, getting appropriate fuel being the other portion.
I wonder if in the future we will think back to this comment and say "man, we were so short sided to not recognize the emerging hobby of home nuclear fission!"
There's also a key difference between uncontrolled fission and controlled fission. Both are bad for your health if you are too close, but one of them is immediately bad for your entire neighborhood/district/city.