Apple doesn't need invasive statistical fingerprinting, they already have your unique ID, unchangeable device serial numbers and apple ID account. An iOS device cannot install any app without an apple ID, and nowadays you need a phone number to create an apple ID which is pretty much
the supercookie identifier in most of the world.
You can see a lot of the tracking and correlating that apple does within their own legal documents, which I commend them for at least writing them out clearly : https://www.apple.com/legal/privacy/data/en/apple-advertisin...
Apple also uploads a lot of logs, etc from their devices to their servers, and opting out of apple level tracking at some basic level is often just not an option. Ex, they upload battery behavior info and use it to improve the battery perf of their devices, or upload people's locations and other location adjacent data like wifi networks with location services and so on.
Apple cares about privacy from third parties, not privacy from apple itself. Which is very apple of apple. Apple also does not let you turn it off in some key parts. And they know they work with security services & authoritarian governments that force them to hand over any data that they have access to, in secret, which gets thousands of innocent people killed, tortured and jailed every day at their scale. Yet they still collect it.
Key parts of apple doesn't really like the existence of third parties in many ways, and if they could, they would rather have full locked down control, from what I can observe from external actions over the decades.
Any large group of people will of course have different actions and motives, and I do commend part of the company for caring, and funding efforts like lockdown mode and keeping %95 of the company thinking and caring about privacy at some level. But that key %5 that does not basically ruins it for many. The best we can hope for is to slowly change that last %5, although with this Services & Ads push, I feel like that bad part is only going to grow worse.