Apple and Google can only control the data shared via the operating system. They can’t control what user behaviors that applications record on the server.
Yeah, it doesn't matter that much if people are voluntarily giving away as many data as possible to an adversarial authoritarian regime. Still, it is disingenuous of Apple to justify its iron grip on iOS apps as a privacy protection measure when it leaves open widely abused API's for years that its users have no way of opting out.