David Ogilvy once distilled advertising genius into four rules: make it simple, make it memorable, make it inviting to look at, and make it fun to read. But more than half a century later, marketers face a new question the ad legend never had to answer: What if “the public” is no longer your primary audience?
For decades, the public meant people—persuadable, emotional, and sometimes fickle. Today, a growing number of agencies are grappling with a more rational but equally enigmatic audience: large language models (LLMs) like ChatGPT and Perplexity. These AI systems increasingly mediate consumer decisions, quietly shaping what products people see, compare, and ultimately buy.
When the Consumer Consults a Machine
“It is one of the biggest shifts we’re seeing in how brands show up in the world,” says Ellie Tuck, creative director and partner at FleishmanHillard. “The fundamentals of trust, quality content, and authority remain the same, but how they are brought to life in an LLM-powered world is undergoing massive change.”
The numbers bear it out. A recent McKinsey poll found that more than 25% of consumers now use generative AI tools for product recommendations. What used to be a mix of reviews, magazine features, and influencer shout-outs is being replaced by algorithmically generated summaries—often with no transparency about how or why certain products are surfaced.
From PR Pitches to Prompt Engineering
This shift has profound implications for advertising and PR. Where once brands invested heavily in courting journalists and cultivating influencer partnerships, the new challenge is ensuring your brand appears in an AI’s answer set. That may require structured data strategies, AI-optimized content, and a deeper understanding of how LLMs ingest and rank information.
In other words, the next phase of brand visibility may depend less on charm and more on machine compatibility. Influence is migrating upstream—into the training data, API integrations, and search layers that feed AI responses.
The New “Personality” Factor
Ogilvy famously observed that “the public is more interested in personalities than in corporations.” In the LLM era, personality still matters—but it’s increasingly mediated through machines. The question is whether your brand’s personality can survive the distillation process of AI summarization—and whether it can influence both human buyers and their algorithmic advisors.
For marketers, that means the old rules of persuasion still apply—but the audience has changed, and the competition now includes not just rival brands, but the algorithms deciding which of them gets mentioned in the first place.
