signing in to the app store, required to download *any* app to an iphone (even free ones), requires an apple id. an apple id requires a phone number, so even putting signal on your iphone means deanonymization.
the prompt to enable a new apple id for app store use warns that logging in will enable icloud backup. this prompt occurs even if icloud has been opted out previously.
enabling an apple id for the app store demands a street address.
I think corporations do exist, it's the collection of people who do want to join them. Of the corporation decision maker being too sucked, you can not expect that there will be nice people to join. (The people do not damage the society.)