While the Airbus A321XLR is still in the future - the aircraft hasn't been certified yet, so Airbus can't deliver any - American is beginning the process of switching its existing fleet of A321T planes into the standard, less luxurious configuration.
Doesn’t help that the product sucks. Delta CEO giving supreme lip service about the desire for their “premium product” or whatever, then the product is like an aging slightly larger seat, sometimes broken screen, and acceptable food or drink. All the while nerfing the already pretty mid reward program.
US companies continue to do whatever they want because US consumers will lie down and take almost anything. Delta did overplay their hand and walked some of it back, but it was still an overall significant nerf.