To be fair these are part of a preinstalled suite of native apps, an extension of the OS, rather than being part of the larger app ecosystem. You could argue that implicitly they have the brand-name in front: e.g. "Apple/Mac Photos" or "iMessage".
Every OS has a "Calculator" or something like "Notes", these are reasonable names. Just like you have Google/Apple "Maps" or "Calendar". It's standard to use such naming for apps within a branded suite.
Yeah, that's basically how I treat Google stuff with generic names: I call them "Google Maps", "Google Photos", etc. When I hear Apple users talk about their music service, they call it "Apple Music".
