They can push contextual ads in so many surfaces: Safari's Typeahead, Maps, App Store, Wallet/Apple Card, Apple TV+, etc...
But the reality is that they can't create a narrative around privacy focused ads without betraying their general privacy narrative. Privacy and Ads are antagonistic concepts. Serving effective digital ads depends entirely on knowing certains characteristics and demographics of the end consumer.
Facebook and Google are better equiped to create a narrative that reconciles ad serving and privacy because their core services are "free". Apple simply can't because their core business is to sell expensive phones and computers. Perhaps customers wouldn't care about getting ads in their expensive iPhones, but once the cat is out, I find hard to imagine a situation where that idea wouldn't be deeply criticized and scrutinized.