>>40331757That's why I think they work best as post game completely optional locations without any new pokemon being exclusive there. It's an easy way to just throw in lots of old pokemon to pad out the dex while remaining "in context" of the world. It can reward players with rare pokemon and keep them rare, without just having them in a cave with a 1% encounter rate.
That being said it will probably never come back, and they probably could have worked on fleeing rates anyways.