Oversimplification of polygons when uploading a dataset with over 500,000 vertices from ArcGIS Pro to ArcGIS Online.

Workaround

Two potential workarounds:

1. Keep the data optimization off as it seems to be the main issue of this and the triangles in the feature layer are shown.
2. Instead of downloading the entire world geodatabase, download the data by each country as it is not going to include more than 500,000 vertices.

Schritte zur Reproduzierung