Yes, this is applicable to MAM-only devices (as well as MDM-enrolled devices with MAM/APP policies) as this is an app specific operation.
It's not really about what Intune considers corporate data, it's what the app itself considers corporate data and it's up to each managed app to define this. Some apps have multi-persona support (like the Office apps in iOS and DA mode on Android) and so delete all data associated with the corporate persona. For apps on Android Enterprise, there is a corporate instance of the app that gets its data wiped.