>>48709179Double Battles are not only faster, but allow for more interesting interactions and sets making them fairly unique and different from standard 1-1 battles, and has the backing of the developers to keep incentivizing it for VGC, adding new tools every gen. Anything more than that is just unnecessary and bloated, added nothing of value except for "just add another Pokemon on the field" with little actually added to the foundation to actually making it stand out. Doubles has a bunch of unique moves added to work specifically for Doubles, Triple didn't get much and was just Doubles but with 1 more Pokemon, it felt lazy. Rotation battles probably just weren't popular enough like Inverse Battles
