This is relying on Apple to act as a regulator of Facebook. That's not Apple's job, and they do a bad job of it. That's the job of the government, which is actually (ostensibly (unlike Apple)) representing the people.
The fact that Facebook can do any spying on you at all (because it can still track you, on your current Apple device, right now) is because government regulators are dropping the ball. It's not Apple's responsibility, it's not something they're good at, and it's not something that they should be doing.
I would contend that so far, Apple has done a better job of ensuring their customers' privacy in the face of other companies that employ dark patterns to try to extract personal information from the device that neither Apple nor Apple's customers allowed them to.
The government, so far, has been rather toothless in terms of ensuring the privacy of people and have issued paltry fines to the companies that amounted to no more than a slap on the wrist and extracting a promise that they'll do better next time (with their hands behind their back and fingers crossed).
The reason I purchase apple devices is because they are the only ones that are taking my privacy seriously.
Government regulators are letting the market decide how valuable customer data is and Apple is saying "it is valuable and our customers value not letting random people getting it." Thus, I am voting with my wallet because in this case, votes for elected officials isn't doing much.
The fact that Facebook can do any spying on you at all (because it can still track you, on your current Apple device, right now) is because government regulators are dropping the ball. It's not Apple's responsibility, it's not something they're good at, and it's not something that they should be doing.