Same as T87621: The Blender File Open dialog triggers OneDrive Files On-Demand downloads except for macOS.
@Leon Zandman (lzandman) in T87621#1152939: The main issue I reported however seems to only happen on macOS, where merely enumerating the files in a OneDrive folder triggers the downloading of those files. And this happens because each file is queried specifically for the NSURLIsReadableKey and NSURLIsReadableKey attributes. I've tested this in a separate application and it can be reproduced. I think this is a bug (or at least an unfortunate side-effect) that has to be fixed. Now this might also be a bug in the OneDrive application. Because querying for those other attributes does not trigger a download. I've contacted the OneDrive team about this, but haven't yet heard back from them. A (temporary) workaround might be to only query for those attributes after a user has explicitly selected the thumbnail view.