I don't know that book personally (just know it by name), but I began looking into positional chess concepts when I was already about 1600 chess.com rating and it wasn't really until 1800-ish rating I started to really grasp positional points deeper than just a few weak squares or outposts.
Real positional chess is about this rating or higher, so I'm guessing the book is more aimed at 1600+ players.
Now with that said, I think you could still read it if you have an interest, don't mind maybe re-reading it in the future and don't mind a challenging read. I think even being introduced to new concepts is useful - even if they aren't 100% absorbed right away.
This is kind of what I did when I read My 60 Memorable Games by Fischer. I began reading that book when I was around 1600 on chess.com and I knew fully well that the book was a bit over my head, but I was okay with reading something challenging. By the time I finished the book (took forever to get through by the way xD), I increased my chess.com rating to a bit over 1800. I was constantly working on my chess and only reading the book on the side, so I'm not saying the book alone gave me 200 rating points, but the learning process certainly helped some for sure
In summary, I never read that book [Art of Positional Play] (so maybe my assessment is completely off here xD), but I'm guessing it is slightly advanced for you right now. That is a good thing though if you don't mind a challenge or coming back to the book in the future too. I say go for it if you have the desire to read it!
Would you recommend it for my rating range (1400-1600 rapid)?
And is it helpful to more advanced players than myself?
Thank you in advance. :)