Most likely is GS trying to cut down on credit card lending, like all banks are now, and this is an easy way for them to do it without saying that they are. Of course they won’t come out and say that, which is probably why there’s no explanation or big announcement for this

More likely it’s GS trying to cut down on their risky investments given the current economic situation. These unsecured 0% internet loans are very risky for banks and have absolutely no reward, and since banks are tightening up their credit card lending this is a good way to cut that down without lowering credit limits or denying applications. Lower sales in this case is exactly what they want - the number of people skipping the 15 because of this is low enough that the decreased risk is worth it for Apple and GS