Of course, you do realize that people aren't just throwing their old iPhones in the landfill. They're either re-sold or recycled. So I'm assuming your actual concern here is about the extra packaging and emissions related to producing and distributing new iPhones, correct?
Also, how far do you want to push the "technically don't need replacement" part? There are people still getting by just fine with a 6 series (or maybe even earlier) iPhone, lol!
Well, I think the benefits of technology like the iPhone vastly outweigh the environmental impact, unlike with cigarettes, which imo have zero benefit to society. So it doesn't seem like any sort of hypocrisy for Apple to keep pumping them out, but reducing the environmental impact while they do so. I mean, I bet with the new packaging, it ends up being the same environmental impact as if they were to cut back to releasing a new iPhone every other year with the old packaging. Maybe even less.