Yeah, I don't get this. I have never spent more than about a minute trying to figure out where to go in an area, and I actually appreciate the more puzzling map design because it's an actual challenge to explore as opposed to glorified hallway simulators of regions like Unova, Kalos, and Alola.
I discussed this on a previous page, but we really should divorce the HM problems from the areas' actual design. Having to carry around an HM slave is a problem with the mechanic itself forcing you to have certain moves/Pokemon on your team, not the use of them in the map design. Think about if you had Poke Ride or Secret Techniques or whatever and you tried to get through Mt. Coronet, would you still have trouble with it? And if so, why?
That's not really confusing as much as tedious, for the most part you get through Rt. 217 just by heading forward and most of that route is optional. You do need to enter this one Hiker's cabin to get Rock Climb IIRC, and I don't like that (DP especially had a problem where the HMs themselves were hidden in difficult to find locations, I myself had more problems with Strength because they didn't do a good job of signaling that Lost Tower was a mandatory area instead of an optional dungeon).