You have to sacrifice screen size to shrink the other dimensions, and they already have smaller screen iPhones. It seems most people care more about big screens than size in that dimension
The GSM Arena review is mostly about the confusion of whether it should still be considered a phone at this size. Ultimately they decide it's just too damn big for a phone.[1].
It had a 5" screen.
Screen diameter is in general a bit misleading figure for phones from different generations as "full screen" phones tend to have a taller aspect ratio and hence larger diameter even with same body dimensions.
Not small enough to be worth the tradeoffs though.