As an owner of an iPhone 7 and a Pixel I'd say there are not many. Google Assistant is way ahead of Siri at pretty much every imaginable task, and Google Photos can do a lot more than iOS Photos.
That said, none of those features interest me much. And I'm not sure how many average consumers they do interest. It's more of a 'oh, that's cool I guess'. I prefer my iPhone 7 still.
Yeah, most people I know do use their 'assistant' to some degree, but it's not even close to crucial for any of them. That said, Siri is a running joke among many of us, so if/when assistants become more important, Apple might have a problem if they don't make some big improvements.
That said, none of those features interest me much. And I'm not sure how many average consumers they do interest. It's more of a 'oh, that's cool I guess'. I prefer my iPhone 7 still.