Sixty-three percent of Brazilian consumers now use generative AI tools — twenty-one points above the United States. Brand storytelling profited for a century from the gap between what sellers know and what buyers can verify. That gap is closing fastest in the markets where the storytelling was imported, not invented.

BCG’s Global Consumer Radar, surveying more than 9,000 consumers across nine countries in late 2025, supplies the headline figure. It also reveals what they do with the tools. Forty-six percent of GenAI users employ them to compare products before buying. Forty-four percent hunt for the best available deal on a specific item. Forty-two percent verify technical specifications the seller provided. Shopping-related GenAI usage grew 35% between February and November 2025. The growth concentrates in the mid-funnel, where brand claims meet buyer scrutiny.

More than 60% of BCG’s respondents expressed high trust in GenAI results when shopping. The figure matters because a tool consumers doubt is a novelty; one they trust is a standard. When the majority in a market trust the comparison output, the brand’s own copy ceases to be the primary text. It becomes the claim under examination.

The adoption map inverts the assumption that disruption starts where the technology originates. Brazil leads at 63%, India at 62. Japan registers 48; the United States, where most of these models were trained, trails at 42. No country that built the technology leads in using it to evaluate brands. The asymmetry that once favoured the storyteller now favours the listener. Brand narrative was an anglophone construction; the tool that interrogates it found its readiest users among the audience, not the authors.

Among Gen Z the preference sharpens further. A Commerce and Future Commerce survey found a third now turn to AI platforms for shopping advice. SEO and paid search were built for a generation that typed keywords; the next one is prompting.

A brand story is only as durable as the cost of checking it.

The mechanism is subtler than simple erosion. A study in Frontiers in Artificial Intelligence surveying 224 Gen Z consumers found that AI exposure and perceived AI accuracy both strengthened brand trust, which in turn increased purchasing. The paper concerns brand-deployed AI: recommendation engines, product suggestions, the infrastructure behind the sale. That is a different instrument from the consumer’s own query tool — but it measures the same thing. Brands whose claims survive scrutiny gain trust they did not have to manufacture. The cost falls on those whose narrative was the product.

Most analysis of AI in retail watches the seller’s side: what the algorithm recommends and what the agent adds to the cart. The consequential shift sits on the demand side. BCG found GenAI is now the second most influential touchpoint in the purchase journey among those who used it; among daily users, it ranked first. No marketing team built that touchpoint. No brand controls it. Consumers assembled it from tools designed for other purposes and pointed it at the claims brands would prefer went unexamined.

Brand storytelling depended on a specific market condition: the buyer’s limited ability to compare claims quickly. Origin narratives and sustainability credentials relied on the friction of verification. When a consumer in São Paulo asks ChatGPT whether one trainer brand’s sourcing claim holds against another’s, the friction drops to the cost of a prompt. The answer may be imprecise. The question is devastating regardless, because the buyer now asks it as reflex, not rebellion.

BCG and Moloco’s AI Disruption Index classifies retail as “breached,” its highest-risk category. Two-thirds of the 238 senior marketing leaders surveyed expect significant disruption to the consumer journey. Retail shares the classification with travel and news: industries where AI compresses discovery and comparison into an interface the incumbent does not own. The classification is not a forecast — it is a diagnosis.

Western brand-builders spent decades exporting the premise that a name and a narrative could justify a price. The export succeeded. The importers learned the idiom. Now they have a tool that checks the claims. What survives the prompt is the product. The rest was always atmosphere.