Didn't 1E only require the druid to have mistletoe/Holley/nightshade (think they are all one in the same) to cast spells? So I guess that would be natural and don't disagree. The Ranger should fall under the same. But at some point they got lumped in with divine intervention. I never agreed with either the druid or the ranger getting their spells from arcane means.
The thing is the ranger is part of civilization not nature. That's why they get spells like silence now but druids don't. They are people and are willing to use people tools like the arcane and metal.
The ranger is man conquering the wild for man's benefit.
The goal is to