Even if they believe in false conspiracies, it still means they're open to the possibility, which makes them more likely to look at the evidence regarding other conspiracies. The examples you mention are very polarized topics and therefore don't promise anything good, but you can remind them of the Snowden revelations, or the fact that Epstein didn't kill himself, and use that as a segue into more difficult topics. The latter is very important. Epstein was kept in one of the most closely guarded prisons, and yet the camera was turned off when Epstein disappeared, which is almost always done deliberately. The implications of that are tremendous, and at the same time, this is something people admit. The guards must have been bribed. That's what Epstein's friends are capable of and that points to something deeply corrupt in the system. Everyone's aware that there's some level of corruption, but this goes beyond that, and the only reason people don't realize it is because they don't reflect on the facts that are already there.

Anyway, this isn't entirely relevant to the discussion. I'm not proposing people use the term "conspiracy denialism" toward normies, but instead among their fellow truth seekers. If a normie stumbles upon it, he might take conspiracy research more seriously.