The execution was just awful. Dev favorites got all the good stuff while the rest was left eating shit assuming they even got anything. Designs were about 75% miss, 25% hit. By the end of ORAS only 4 Megas saw any real competitive use.
It was clear GameFreak had absolutely no idea how fix all of this mess, especially the competitive side. Daily reminder they thought fucking Crabrawler would fix the meta
https://youtu.be/fpfRTWisNdYScrapping the whole thing was the correct thing to do.