Question for OP. What would be your guess that someone like he article writer is able to make the inference that Bing being down was also impacting DDG or ChatGPT ?

Is it public knowledge that they use the Bing backend to do their work ?

Particularly for Bing Copilot, isn't the relationship the other way around (OpenAI has the core sauce, bing uses its API to power their copilot searches) ?