>>47200978Actually it wasn’t set in stone. The director of the anime at the time, Tetsuo Yajima, said when they got word of Sun and Moon it came as a complete surprise. When they started making XY&Z they originally thought they had another year left to finish everything, when in reality they only had a couple months so they had to rush through the story beats and XY&Z became shorter than it was supposed to be.
They even planned on the 20th anniversary movie to have all of Ash’s companions together but again, being blindsided by Sun and Moon, the cast would be too bloated and they couldn’t figure out how to write a scenario where they would all come together.
It’s actually quite sad. Gen 6 was probably the most rushed generation ever.