How to remove Esri Basemap Credits in ArcGIS?
In this post you can find the easy steps to follow for removing or modifying the service source layer of an any WMS. Particularly the text in the picture 1. However by my experience it is not a good idea to hide sources because if a WMS is free in internet mean that you can use that layer for your project. Personally I never remove the source service layer credits but in the most of cases I move it from the original place and I change the font size and color.
Steps:
Switch the ArcGIS into Layout.
Once you click that menu, you can see that the text of Service Layer it is divided from the layout and you can move it (modify, change size,color) and if you just move the text outside of the Layout space it will not be displayed in printed map (or PDF export).
Youtube Video 👌
