What I do see now is the rise of "microwave auditory effect" accusations, where the government or some other clandestine organisation is using radio waves to create voices in their head. Obviously, these are a lot harder to disprove, requiring a wideband SDR and expertise in operating one to conclusively rule out, something far less common than modern medical imaging.
Additionally, it's dubious that the subject would believe you even if you put them in a faraday cage and showed them the blank waterfall view proving no radio transmissions are even occurring. Owing to the nature of schizophrenia, they'd move onto the second-most common allegation I've seen: "psychic attacks", an accusation that handwaves away all physical explanations for the percieved harassment with an ill-defined mysticism that cannot be fully explained.
I often wonder myself how I would handle schizophrenia, and if the heroic mental gynmastics it creates are merely a product of a large ego, unwilling to admit one can be wrong in their judgement...or are genuinely organic/structural in the brain.
I don't know how accurate the movie was, but the movie A Beautiful Mind explored the topic of thinking your way out of schizophrenia. Its well worth a watch if you haven't seen it.
https://mentalillnesspolicy.org/medical/poor-insight-in-schi...
Unfortunately, thought disorders are pretty hard to for the patient to understand they need treatment for.
Anything that shows what they say isn't true will be considered another layer of the targeting and campaign against them, furthering their conviction they're being targeted. Quite simply they're torturing themselves.
It's sad, but I wonder how do you help someone like that?