Different assistants read different indexes
They are not all looking at the same web. ChatGPT's search leans on Bing's index. Google's AI answers work from Google's index and its Knowledge Graph. Grok leans on the live web and the conversation happening on X. Claude draws on what it learned in training plus its own web search, and Perplexity runs its own crawler. That is why a business can turn up in one assistant and be missing from another, and why checking only one of them tells you very little.
