According to TechCrunch, data that is collected is aggregated and anonymized, and there is an opt-out option for new customers.
"You may be eligible for certain Apple Card programs provided by Goldman Sachs based on the information provided as part of your application. Apple may know whether you receive the invitation to participate and whether you accept or decline the invitation, and may share that information with Goldman Sachs to effectuate the program. Apple will not know additional details about your participation in the program.
Apple may use information about your account with Apple, such as the fact that you have Apple Card, for internal research and analytics purposes, such as financial forecasting. Apple may also use information about your relationship with Apple, such as what Apple products you have purchased, how long you have had your Apple ID, and how often you transact with Apple, to improve Apple Card by helping to identify Apple metrics that may assist Goldman Sachs in improving credit decisioning. No personally identifiable information about your relationship with Apple will be shared with Goldman Sachs to identify the relevant Apple metrics. You can opt out of this use or your Apple relationship information by emailing our privacy team at firstname.lastname@example.org with the subject line "Apple Relationship Data and Apple Card."
Applicants and cardholders may be able to choose to share the identified metrics with Goldman Sachs for re-evaluation of their offer of credit or to increase their credit line. Apple may share information about your relationship with Apple with our service providers, who are obligated to handle the information consistent with this notice and Apple instructions, are required to use reasonable security measures to protect any personal information received, and must delete the personal information as soon as they have completed the services."