Workers don't exactly decide to collectivize in situations where the status quo is comfortable and they already feel like their voices are heard. It's almost a sense of "if there isn't a workplace democracy we'll make it one".

If anything an adversarial relationship with upper management precludes attempts to organize as it implies they failed their boots on the ground in some way and the problems got so fad they felt there was absolutely zero "internal" channels available to get the changes they want heard, let alone enacted.

Apple employees aren’t unionising because of poor working conditions in Apple stores. It’s generally considered one of the best employers for retail staff already.

They are unionising because Apple has money and the employees would like some more of that money. No judgement, but both sides here are simply motivated by financial self-interest.