It’s All Integrated
Apple Pay is a fairly secure platform. Fraud isn’t impossible on it, but it is much harder to pull off than with standard credit or debit cards. For the most part, that’s because the weak link for most credit card or debit card fraud has been the issuing bank.
With Apple Card, the entire platform is much more integrated. Apple handles more of the actual process, effectively becoming its own bank. That should shore up any weak points on an issuer’s side, and it will make it much easier for users to deal with any actual fraudulent activity.