>>39189807They never adopted it during the 3DS lifecycle, even though by all means they should've been able to add additional forms or ultra beasts retroactively to Sun/Moon instead of having them exclusive to Ultra Sun/Ultra Moon.
It seems that they literally do not know how to develop a base game as a platform for extendibility. If they don't learn how, whatever game they develop after Sword/Shield is doomed.
Pokémon as a core series is no longer in a position that it can get away with standalone releases on an almost annual basis. The upset with Sword/Shield cutting out large numbers of national dex could result in Ultra Sun/Ultra Moon having a continued presence in the competitive scene and a reduced adoption rate of Sword/Shield competitive.