cbwjm
Seb-wejem
I don't see how the assumptions are North American as North America has a lot of nonforest wilderness. A lot of it.
Actually the whole class is defined as a forest ranger.
Armor: Defaulting to light and medium armor leans forest. Arctic rangers would wear heavy armor to protect from the cold and stealth would be less of an issue as there is a lot less of it in the snow. Desert rangers might not wear armor at all and have Unarmored Defense.
Weapons: Archery and TWF are tilted to forests. The lack of Great weapon focus that would lean to mountain and hill rangers is lost.
Spells: Sea, sand, and snow spells always come to ranger very later in an edition's life cycle.
Features: Although they work, sand, snow, and water are not mentioned directly in ranger class features.
DMG: Natural hazards and challenges in the arctic, desert, coast, and swamp are barely mentioned. This further tilts how rangers are seen.
This is why I'm currently the option voter for the last option. Every edition's ranger to me is way too narrow in scope.
Currently, I'm working of a class feature variant to replace fighting styles that changes how a ranger fights based on their favored enemies and terrain.
BGS'sroute is okay for a video game but still bad for an RPG
I gotta say, I really disagree with everything here as I don't see anything that you mentioned as defaulting it to forest over other regions.
While I'd like more fighting styles, the current ones don't default it to a forest build. I don't think that an Arctic ranger would be necessarily wandering in heavy armour to keep warm, that would be covered by cold weather clothing.
I don't think that sand, snow, and water need to be directly mentioned to make the ranger suitable for those locations. Want to camouflage yourself in an Arctic or desert environment? Those are natural materials so go at it.
Sea, sand, and snow specific spells might come to them later in an edition life cycle but that's true for all classes. As is, the spells they start with still work without issue in those regions.