Most people who I know that think the CIA invented bitcoin, are not very familiar with the pre-history of Bitcoin including work by Back, Szabo, Finney, etc.

I'm not saying that certainly no intelligence agency created Bitcoin, but rather, I'm very skeptical of the certainty that many people have around that topic.

Because, when you are somewhat familiar with that pre-history and look at it from an engineering perspective, you can clearly see the pieces gradually falling into place. In the1980s there was work by Chaum about how to build a database run by mutually suspicious entities. In the 1990s there was work by Back for proof-of-work. As things moved into the 2000s, there was Szabo's Bit Gold, which is very similar to what Bitcoin ended up being, and Finney's Reusable Proof of Work "RPOW" tokens. Finney hadn't solved the centralization issue, and Szabo hadn't solved the issue of better computation causing supply inflation over time, but they were collectively within shooting range of the solution. Others as well. Meanwhile global bandwidth was getting better, encryption in general was getting better (and there we've got an actual intelligence agency contribution), etc.

And then Satoshi added to that work, including the difficulty adjustment in particular and many other details, with a full implementation.

Basically, if someone thinks that Bitcoin just kind of magically came out of nowhere, then it's pretty easy to see how they'd be inclined toward a conspiratorial assumption.

However, if one sees that, just like any other industry, there was a series of engineers building on each others' work until someone finally got it over the line, then it looks a lot more organic.