In arcscene, all you have to do is right click the layer--> properties --> rendering tab --> and select 'Disable material textures'. I can't find the equivalent in Pro
strange, the only reference with those key words is in What's new in ArcGIS Pro 1.1—ArcGIS Pro | ArcGIS for Desktop
and it is associated with Layer 3D To Feature Class—Help | ArcGIS for Desktop
but you could start in the latest 'whats new' and work your way back in case I missed something
What's new in ArcGIS Pro 1.3—ArcGIS Pro | ArcGIS for Desktop
I found a workaround by exporting the layer to a shapefile since shapefiles do not support layer texturing.
Many years after, and without converting to shapefile, is possible to get rid of the texture in arcgis pro.
In the symbology menu, when you choose the symbol to edit, choose properties --> appearence. Material mode is set by default to Multiply. Just change to replace and the texture will be gone 🙂
Thanks! This took me two hours of nonsense googling, trying and failing. And then the solution was that simple....!