Monopsony chickenizes whose groups of workers, even whole industries. Amazon has chickenized publishers. Uber has chickenized drivers. Facebook and Google have chickenized advertisers. Apple has chickenized app creators.
Apple is a monopsony. So is Facebook.
Market concentration is like the Age of Colonization: at first, the Great Powers could steer clear of one another's claims. If your rival conquered a land you had your eye on, you could pillage the one next door.