Hi @delongtime As noted below, we have an enhancement request open for this [ENH-000135498: Better display of symbol preview or legend when conflicting visuals happens either through visual variables, scale based sizing, or attribute driven symbology.] While you could call technical support to be added to the request, perhaps an easier thing for you to do would be to submit an idea in the Pro idea exchange that demonstrates the type of attribute-driven symbology you're using in your maps and explains what you would expect to see in the legend given that the symbology can vary per feature. Adding specific examples about the way you're working with attribute-driven symbology and your expectations for what you would like to control and visualize in the Contents pane/legend will be very helpful.
Once you submit the idea, we can associate that with the existing Enhancement Request on the backend so that we're tracking this feedback together.
Thank you for the willingness to provide constructive feedback!