The smallest iPhone would've been classified as a "phablet" a decade ago
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.