I think it would be a good idea to add cleaning for GeForce Experience as the /ProgramData/NVIDIA/Updatus/DownloadManager folder can get very large with old driver downloads. I don't know if the program deletes old drivers itself after a certain amount of time or when the folder reaches a certain size, but only the latest driver can be reinstalled from the program so theres no need for the older ones.
If you know for sure wiping out the contents of that folder are safe you can add it into CCleaner:
1. Options -> Include
2. Cleaner -> Advanced -> Enable/tick the item Custom Files and Folders
-or-
You can request a winapp2.ini cleaning routine be made for it if it doesn't already exist in winapp2.ini.