I don't remember that one. Link on it?
Seems in my recollection I mixed up multiple failures of nvidia's patent trolling with a specific legal dispute Apple lost over Macbook GPUs.
Nvidia caused a huge issue by providing apple with defective macbook GPUs that ended up costing Apple a ton of money, which nvidia refused to reimburse Apple for. This seems to be what precipitated their removal from all Apple products.
In addition, nvidia repeatedly filed patent lawsuits against some of Apple's closest partners, including Samsung and Qualcomm, and lost.
Apple does not want to deal with having defective nvidia products which nvidia then refuses to replace or reimburse Apple for, and Apple does not like seeing its partners drawn into frivolous legal disputes that cost large sums of money to fight with zero actual gain for any of the companies involved. Thus, Apple has decided nvidia will no longer be a partner for any future products.
Apple has always sought a second source for all of the components it uses in both Macs and iOS devices. This is a well known fact. Apple sources from both Samsung and TSMC foundries. They source from both Qualcomm and intel for modems. They source from both Finisar and Lumentum for optoelectronics. They source from both Broadcom and Skyworks for ISPs and digitizers. If it wasn't for nvidia's scandalous business and practices, they would continue to source from both AMD and nvidia for GPUs.
You must not know much about Apple to claim they "prefer a single vendor".