Apparently 16GB iPads set the line at 5GB per app by default, and while that flag lets you request more they don't make any guarantees of how much extra quota you will get, so I'm not sure how useful that is for loading a big model if it might randomly fail. I suppose it's probably safe to assume the Vision Pro is similar.
https://9to5mac.com/2021/06/25/apps-can-request-access-to-mo...