I have tried removing labels but the light grey canvas basemap doesn't have the ability to remove labels, they are still there in small letters (often, multiple labels for the same river so it is very annoying). I have not been able to find a basemap that has no labels anywhere and I really need just a basic basemap with the detail of the light grey canvas but no labels that I can use in ArcGIS. Thanks!
World Light Gray Base: This map was designed to draw attention to your thematic content by providing a neutral background with minimal colors, labels, and features. Only key information is represented to provide geographic context, allowing your data to come to the foreground. This light gray basemap supports any strong colors and labels for your theme, creating a visually compelling map graphic which helps your reader see the patterns intended.
Tile Layer by Esri
The Terrain With Labels basemap allows you to turn off all labels, as does the Oceans basemap (this doesn't seem to be a default basemap in ArcGIS Pro, but you can add it from this URL: Ocean/World_Ocean_Base (MapServer)).