The topic, in general, might be summarized as "Why is it that the FBI seems to have known about most of these mass-shooter cretins in advance of their moment of infamy?" Because--spoiler alert--they have.
I miss having Will Grigg's voice available for these increasingly predictable events. He'd say it far better than I ever could. (Not that I don't try... :-)
For anyone who hasn't already figured this out, the key to context here is to understand that the Fibbies' prime directive is ultimately to be on-retainer, on-call propagandists for their funding masters in the Department of Just-Us. Success in that role guarantees their continued existence; it purchases indemnity for whatever means they need to justify the end; and it provides plausible deniability and the appearance of legitimacy and professionalism to both sides. In the world of politics, it's a pretty slam-dunk arrangement to be in.
And, in the age of "all the news that's print to fit" (itself a similar and parallel arrangement of political power players), the best way to have ongoing and continued success in this role is to maintain, at all times, a grab-bag of ready-made candidate possibles for exactly the sort of Enabling Events which can push an otherwise flaccid narrative into legislative or bureaucratic reality. Just locate either an already-radicalized creep or an easily-radicalized dupe with infiltrators and CIs, and keep deliberately marinating or simmering him in hatred and angst until needed.
Keep enough candidates in play, and when the request for support comes from above, it's pretty trivial to just push the pre-calculated-tipping-point buttons in the candidate pool and then simply look the other way until something awful happens.
I hate to say it because the people designing and arranging this game are nearly incomprehensibly evil to any human being not irreparably broken by politics, but it's actually pretty damn brilliant gameplay. When hitting the GO button in a sufficiently large pool of possibles, the likelihood of something not just happening, but happening at the right time, is high, and of course for political Enabling Events, two-fers and three-fers are hardly "bad". The "news that's print to fit", and the reality of de facto internet censorship by Big Tech, has got the G-man's back against accusations of incompetence, or malfeasance, from Us The Unwashed. And of course at any time after sufficient political damage has already been done, Dudley Do-Right can then come riding in on the white horse and be conspicuously seen Saving The Day by bravely and oh-so-publicly rounding up as many [of his own carefully cultivated] candidate-pool members as he may need, to re-establish his bona fides and competency as a Valued Contributor To Society.
I mean, think about it. The puff pieces just write themselves: "Wow, look at how fast our Noble Warriors caught these other, similar creeps! ZOMG, this must mean that creeps just like that are already everywhere, so we must Do Something Now!", or maybe, "Our Pious Protectors have shown their bravery today by Preventing Other Imminent Attacks, but they are Desperately Underfunded And Need Our Help And Love Now More Than Ever"...
On the operations side it's all win too: rounding up the known, already-infiltrated, carefully-cultivated suspects is far less risky or difficult than going after (or even wasting time looking for) any truly independent creeps who don't need any help getting to their own destiny. Naw, that shit's dangerous; the strategy there is just to let those come when they may, and then cynically mine the aftermath--for new candidates for the ongoing possibles pool.
Rinse, repeat. The "real work" isn't really in investigation or apprehension (or heaven forfend actual peacekeeping), but in radicalized-creep farming, from planting to harvest.
All this is of course nothing new, even if "we" seem to be...modernizing it at an accelerating rate; it is, rather, right out of the playbook of the classic protection racket, which has been around pretty much since there have been humans. And once you apply the lens of the protection racket to what you're looking at, you essentially understand everything you really need to know about politics.
So: of course the FBI knew about the Colorado creep. It's their business to know.