Some comments seem to be optimistic about the potential change from Apple. But once Apple relax webkit requirement from app store, it will mean all "do not track" cookie enforcement would be easily worked around.
The default can still be Safari, not "all" enforcement will be worked around. We simply can't trust Apple to do the right thing without supervision, though. As we've seen with the App Store, Apple uses these positions of de-facto authority to disempower the user and reinforce their own profit margins. We let them fly by the seat of their pants for too long, regulation is long overdue for this business (and app distribution sector as a whole).
If you want to opt-in to Apple's protective blanket, do so. It's not an excuse to weld over the safety hatch for the rest of us.
The default _browser_ will mostly be Safari. But the moment webkit requirement is relaxed, all in-app browsers for Facebook, TikTok, Youtube, Instagram, etc will be replaced with their own forks without any respect for "do not track". They will become the second most used browsers on iPhone, not Firefox or Chrome.
If you want to opt-in to Apple's protective blanket, do so. It's not an excuse to weld over the safety hatch for the rest of us.