Finite lifespan and batter don't degrade on a new iPhone that happens to be last years model.

The "fashion" element is BS. Almost no one can tell what iPhone is which.

It's literally the same phone now or 6 months from now. It doesn't "expire". You're really stretching here.

Same thing is true for Android and pretty much most electronics or TVs.

Okay, sure, if you don't personally value the things other people value that decrease over time, then it wouldn't make sense for you to buy things at full price.

Other people value those things, and can in fact tell the difference, and thus buy full price iPhones.