The colors of Google's AI Overviews are designed to reflect specific journey types and the query intent itself. According to Google, the color choice is more about the user's journey and the intent behind their query rather than an indication of the confidence level of the response.

No, the color of the AI Overviews does not indicate the confidence level of the response. John Mueller from Google clarified this point in a statement on May 21, 2024, emphasizing that the colors are unrelated to confidence and are just for fun, aligning with the journey and intent of the query.

Google chose to use different colors for AI Overviews to make the feature more engaging and to visually represent the type of journey a user is on and their search intent. The color variation is a design choice to enhance the user experience by associating different colors with different types of search journeys and intents.