Im not sure this is a good metaphor. None of Apple, Amazon, or Google (no matter how hard they try) are social media companies. None of them are in direct competition with Parler, and shutting it down wont increase their market share one iota. None of the social media companies are banning people because of things they said on Parler, and I doubt that the pressure applied to Apple/Amazon/Google came from outside the companies, this is most likely the result of engineers working on the AWS team pressuring their bosses, and it snowballing.