Google’s use of their Android sharing icon in their iOS apps has nothing to do with “open” nonsense and everything to do with Google asserting that they know better.
Apple shamelessly pulls the same move — see, for instance, every Windows app they’ve ever made — but they don’t patronize us with bullshit justifications.
I went to art school. I’ve seen people dream up some conceptual nonsense to fit whatever piece they threw together the night before. I can smell bullshit.
If you want to stay “on brand”, just say so. That’s why the new Google Maps looks the same on iOS and Android: all Roboto all the time, “material” design, and a vertical ellipsis to denote “more” in the toolbar.
(And by “their Android sharing icon”, Arment means Alex King’s sharing icon.)