When it comes to those "detailed plans", if you actually try something like that, what you get from it is a very broad outline that is pretty much a mish-mash of common sense stuff and cultural tropes (many of which aren't true IRL). Similarly, the "list of targets" that it makes is simply the most prominent people associated with that area in public perception, not necessarily people who are actually key. All of this can be achieved just as well with a few Google searches, and the resulting plan will likely be much better for it.
I've yet to see any example where GPT would come up with something along these lines that is not trivially found on the Internet anyway.
And if you wanted that on paper - or on your Kindle - Amazon is happy to oblige:
Similarly, for homemade guns, there's e.g. FOSSCAD (and there are many forks of that repo on GitHub even):
Or for something more oldschool, search for "expedient homemade firearms". I got my paperback a few years ago from Amazon, as well (sadly gone now, but some derivative works are still around if you look).
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