The Occam's explanation here (yours) is most definitely the correct one. I can't imagine the executives of these companies sitting on conference calls coordina

The Occam's explanation here (yours) is most definitely the correct one. I can't imagine the executives of these companies sitting on conference calls coordinating their decisions like some sort of technocratic United Nations. That's just not how things play out in reality. If anything, it's more likely people are tasked with monitoring public opinion on what other companies did. If the public reacted well, then the same thing may be implemented. There's no cabal, just people watching the news and thinking "well that's a good idea that people like".