I'm having a problem with ArcGIS Pro not showing symbology for a layer I'm trying to display. I have the Census Zip Code tabulation shapefile, which I have joined to a .csv that shows constituents in each Zip Code. The fields have properly joined and the Symbology is showing values for the breaks. However, it is not showing them on the map. I've attached a screenshot of my desktop.
Mark - I downloaded your zipped data and reviewed the video and was able to replicate your experience as well. I then saved the *.csv to a *.xls document and did the workflow again. My redraw performance was less than a second vs. not drawing at all with *.csv. (or least incredibly slow redraw). I suspect it's a BUG and would recommend you reach out to Esri Support Services to log it. I'm using ArcGIS Pro 2.1.2 for my release.version.
This is consistently reproducible behavior when trying to symbolize use joined fields using CSV. Using XSLX is hit and miss.
1. As Dan said, create a new feature dataset with the joined data included.
2. Since that isn't always desirable, "all" you have to do is select the joined field you want to symbolize and if it doesn't appear, click the Set an Expression button right next to it and either add zero (+0) or subtract zero (-0) at the end of your field. No actual change to the values, but it suddenly works.
Here's a video demonstrating: nosymbologyjoinedfields.mov - Box