Text Measures and Date Time Measures cannot be used in Segmentation. Segmentation is the process of creating filtered audience segments based on calculated insights. Calculated insights are metrics that define and calculate multidimensional measures on your data. Only Numeric Measures can be used as calculated insights, because they can be aggregated using functions such as SUM, AVG, MIN, MAX, or COUNT. Text Measures and Date Time Measures are not types of measures, but types of dimensions. Dimensions are fields that can be used to group or filter data, but not to perform calculations. References: Measures and Dimensions