So you think a Ranger and Druid wouldn't know anything at all about Nature because that's what you are saying, same goes for the Priest not passing Religion checks. You people assume every single check it's going to be just about having Insane Knowledge about a specific topic which is dumb as hell. There should be at the very least some flexibility when it comes to these kind of checks.
I agree, it does make sense for the Druid and Ranger classes to get proficiency in Nature, and for the Cleric and Druid classes to get proficiency in Religion.
And you know what, they do get (the option of) proficiency in these skills whereas fighters, for example, don't.
A druid with poor memory/book learning (intelligence) but high perception and intuition (wisdom) should be worse at recalling nature lore than a druid with good memory but relatively worse widsom.
The former druid, however, would be better at survival checks.
I agree with the flexability of using different stats for skills, but that would be a lot more work to code and probably result in an even more clunky UI.