This turned out to be an erroneous handling in the implementation of func tabBarController(_ tabBarController: UITabBarController, shouldSelect viewController: UIViewController) of UITabBarControllerDelegate. Thus this all question can be ignored. Apologies.

Apple, please, prioritise this issue: It is slowing down the developing/debugging process. Thanks!

I am experiencing exactly the same and I cannot find a valid solution to resolve this. Similarly to d.jeon, this issue manifested with the iOS15 and Xcode 13.0. Is it an iOS 15 bug? And is it expected to get fixed by Apple? Thank you for your response.