>>26660838megas cause more open problems than solutions. They will be reconned in favor of a single, stat boosting held item.
Mega stones will just begin to clutter the item bags. designing megas just takes time away from designing new pokemon. Pokemon that actually NEED the stat boost from a mega, arent prioritized, see flygon. Flygon a gen 3 dragon that is horrible stat wise compared to its other dragons and garchomp a similar typing dragon needed the stats from a mega, but was denied one because sugimori and his team couldnt make a proper design for the pokemon. Needless to say there will be countless pokemon that need a stat boost but wont get megas because the design team cant make a proper design. So instead we will see a temporary stat boosting item. to be held by the pokemon.