I built a very simple Python GP script tool in ArcMap 10.4.1 that takes a user input file (e.g. csv) and returns a Point Feature Layer using XY coordinates from the input file.

After I published the results as GP service (no map service returned), I used Web AppBuilder 2.3 (Dev Edition) and set up my GP widget to return the output as an operational layer.

After I run the GP widget and get the result mapped, why am I not allowed/able to change the symbology of my operational layer?