American has several joint ventures, including a transatlantic joint venture with British Airways, as well as a transpacific joint venture with Japan Airlines. In general airlines do everything they can to create metal neutrality on joint ventures flights, since the intention is that airlines share revenue and coordinate schedules.
So it’s not unusual to see airlines align services in the markets. The always knowledgable @xJonNYC reports that American Airlines is improving service on flights between the US and Japan, so better align with JAL:
We are excited to further align the inflight experience for customers traveling on both American and JAL with new Japanese meals on flights departing North America to Japan. The meals are the same as those served on JAL flights and feature a “bento box” appetizer and three that includes rice and miso soup. The meal is available for preorder on aa.com or by contacting Reservations at at least 24 hours before flight departure. In addition, spirits are now complimentary in the Main Cabin on all flights to and from Japan.
As you can see, American is aligning their Japanese meal options with what JAL offers their passengers (though unlike on JAL, you need to pre-order the meal), and American is also introducing free spirits in economy on flights to/from Japan (currently only beer and wine are complimentary).

Japan Airlines business class bento box
Now if only they’d align the important things, like the crews and onboard bidets. 😉

While a bit more niche, American and Japan Airlines are also adding priority handling for their top members:
The customer experience is always on our mind, and that’s especially true for our VIP customers. In May, American implemented a process to assist top JAL customers flying codeshare on American to and from Japan at DFW, LAX, and ORD which is modeled after our Five Star Service, including guaranteed arrival, departure and connection assistance. Likewise, JAL will soon begin to assist our ConciergeKey members on select JAL flights at NRT and HND, followed later this year by Kansai International Airport in Osaka (KIX).
These are all fairly minor upgrades, though I still figured they were worth passing on.
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