In practice, GEO shifts three things: content shape, technical exposure, and measurement. Content moves from broad, keyword-heavy pages to narrow, direct-answer pages — one intent, one clear answer, up front. Technically, you add structured data and llms.txt and make sure crawlers like GPTBot and PerplexityBot aren't blocked. Measurement shifts from keyword rankings and click-through rate toward tracking whether your brand actually gets mentioned inside ChatGPT, Perplexity, and Gemini answers — a much fuzzier, still-emerging discipline.
Nothing about backlinks, site speed, or topical depth stops mattering; GEO just adds a second output format to optimize for.