^^ I think that's probably accurate, especially outside the US.
The M4 is kinda the "defacto" AR15 most of the world sees due to US and some NATO .mils. If we didn't have the NFA I'd bet money 14.5 would be one of the most popular barrel lengths in the US.
16" and 18" AR's are SPR length. (obviously there's a LOT of variations of barrels in those lengths in the US, but that's somewhat NFA related) At least it is in .mil's these days. THe Marines still have some M16A4's, but they are small and weird. To someone not steeped in US AR culture, a 16" or longer barrel is the DMR version of an AR.
AK variants seem to have stayed with 16ish" barrels for the -74 and -74M, but there's a ton of -74Us running around out there too.
A Krink or M4 is perfectly capable out to 250-300m, so I can buy calling a 16" or longer barrel a "long range" variant.