Google Ads added a new paragraph to the AI Max help documentation for AI Max keyword prioritization." It explains that when "disabling the broad match campaign setting or moving to AI Max, broad keywords are not treated as exact match keywords in prioritization." It then tells you how to handle this within AI Max.
Google wrote:
When disabling the broad match campaign setting or moving to AI Max, broad keywords are not treated as exact match keywords in prioritization. To maintain this keyword prioritization without the broad match campaign setting enabled, add copies of exact match keywords in your new AI Max campaign (broad can be converted to exact, but that will remove historical keyword stats). If the standard prioritization of exact match keywords in AI Max is preferred, no action is required.
So you need to add copies of exact match keywords in your new AI Max campaign but the historical data will be lost.
This red box was added to the document, as far as I can tell:
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