>>38236357Either Gen 5 or Gen 6.
Gen 5 is a contender because it was the start of "HEY, HERE COMES THESE CHARACTERS TO STOP YOU IN EVERY AREA TO TALK ABOUT THE STORY YOU DON'T CARE ABOUT," along with forced participation in side content and trainers with small parties.
Gen 6 is a contender because it took all of Gen 5's huge flaws and ramped them up big time without any of the redeeming qualities. More story interruptions, more railroading, and gimmicks.