There is no way for apple to prevent apps from tracking, since many apps require persistent storage. At best Apple can throw apps out of the appstore after they

There is no way for apple to prevent apps from tracking, since many apps require persistent storage. At best Apple can throw apps out of the appstore after they become aware of an infraction. I believe this dialog does control access to apple's advertiser-id (IDFA), so apple did implement some technical measures. Unfortunately that's not the only way for an app to track a user, so giving the impression that Apple enforces this denial would be misleading. People already blame Apple for apps lying on their privacy labels.