This only applies to Mail, Messages, and Safari Private Browsing. It does not apply to third party mail, messaging, or browser apps; nor does it even apply to regular/standard browsing in Safari.
This just feels like a cat and mouse game to me. Apple will somehow need to know what are valid tracking parameters to remove from the URL (i.e. remove the 'gclid' parameter, but not things like 'productId' or 'userId'). They really have no way to know which parameters are essential for the page to load correctly, and which ones are just extra fluff used for tracking. My guess is they'll need to maintain a list of valid or common tracking parameters somewhere.
Nothing is stopping Facebook, Google, or other advertisers from creating new parameters so that they could go undetected until Apple updates their tracking protection. Or maybe companies will start using short URLs more often to hide all the parameters. There are other ways to track as well...cookies or by IP address.
Apple's iOS 17 update includes a new feature called Link Tracking Protection, which automatically removes user-identifiable tracking parameters from URLs. | Jun 24, 2023
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Explore the latest iOS 17 privacy updates and its impact on marketing practices, including Apple's Link Tracking Protection.
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