iCloud & iCloud Photos · Storage Studio and iCloud
Does Storage Studio work if I use Advanced Data Protection for iCloud?
Short answer: Yes. Storage Studio works with iCloud Drive's folder on your Mac through macOS itself, never signs in to your iCloud account, so Advanced Data Protection doesn't change what it can do.
Yes. Storage Studio works with the iCloud Drive folder on your Mac, the same way whether or not you've turned on Advanced Data Protection. It doesn't read your iCloud account over the internet and never needs your Apple Account sign-in, so the setting doesn't change what it can do.
Making files online-only, finding duplicates among downloaded iCloud files, and measuring space all happen on your Mac through macOS itself.
Advanced Data Protection is managed in System Settings → your name → iCloud. See is Storage Studio safe with iCloud.