I've added ownCloud to special folders. Not using it anymore (nextcloud...) how do I remove ownCLoud?
The (cropped out) list under that one is the one you can manually add/remove things to, for cloud folders that aren't autodetected.
The top list shown in your screenshot comes from the Windows registry. If that program was removed, it left parts of its registry settings behind which still flag it as a cloud folder.