I don't understand why Chrome even does up-front permissions. iOS got this right from the start: ask on the first attempted access of the gated resource, allow

I don't understand why Chrome even does up-front permissions. iOS got this right from the start: ask on the first attempted access of the gated resource, allow the user to grant the permission once or on an ongoing basis, respect the choice. Don't allow permission prompt spam. Even Android recently moved to this model from up-front permissions, so Google is aware of it.