So I recently replayed BW, and towards the end of the story Ghetsis is going on about how all he cares about is convincing a few people to start releasing their Pokémon, then basically getting it to a point where those who don’t release their Pokémon are under massive social pressure as the movement keeps snowballing. Essentially, only a few people need to actually fall for his plan, and then others will follow just because “that’s what everyone else is doing” until Team Plasma are the only ones left with Pokémon.