New research confirms what many marketers have suspected: consumers respond well to AI-generated content until they know it is AI-generated. Once disclosed, trust drops and engagement falls by as much as 35 percent. The disclosure gap is becoming one of the more consequential brand risks in AI content strategy.
The challenge for brands is that they cannot control when audiences make the determination. Disclosure is increasingly happening anyway, because audiences are getting better at recognising AI content without being told.
Research published this week by MarTech confirms a pattern that has been building across multiple studies: consumers rate AI-generated content positively when they do not know it is AI-generated. When they find out, trust drops sharply and engagement follows.
The numbers are specific. YouGov data from 2026 shows 32 percent of consumers say they would trust a brand less if they knew content was AI-generated, compared with just 15 percent who would trust it more. Capgemini research tracking sentiment from 2023 to 2025 found trust in AI-generated content dropped from 73 percent to 55 percent in two years. Content that audiences perceive as AI-made carries an engagement penalty of between 20 and 35 percent compared with human-created alternatives.
Separate research from Klaviyo's 2026 AI Consumer Trends Report found only 13 percent of consumers completely trust AI. The overall picture is consistent: the content itself can perform fine. The problem arrives when the disclosure comes.
Share of consumers who say they would trust a brand less if they knew its marketing content was AI-generated — YouGov 2026
Why it matters
For Australian marketers using AI to generate content at volume, the research introduces a structural problem. The content can test well in isolation. The brand association can be damaged by the method of production becoming known. Given that AI content is increasingly recognisable by style, cadence and certain visual signatures, brands cannot reliably assume the disclosure stays hidden.
Australia's ACCC has already flagged AI-generated content as a focus area for its 2025-26 enforcement priorities. The combination of consumer distrust, platform detection tools and regulatory attention creates a layered risk for brands that are relying on AI volume without a human-voice layer.