I'd say music is always manipulation as it's always triggering emotions in some way. Unless it's some genre or band you absolutely hate. But even then it's triggering emotions, just probably not the intended ones. :-)
When your parent put sugar in a cake, they you to enjoy the cake for you own enjoyment. They will dose the cake, and make you experience the cake in this context.
Kinder wants you to enjoy it so you buy it again. The goal is not the enjoyment but the reaction after it. Dosing the sugar, the other ingredient, the context you will consume it and the so on are going to be completely different.
When you hear "Ride of the Valkyries" being played in apocalypse now, you don't hear the voice of the director suggesting "now you should feel this particular way, because I said so". You just enjoy the craft.
Some movies and series now, it feels like the way they put music, cuts, etc. are just cheap plots designed by engineers to get something out of you.
You can't feel the desire of creating and sharing something, rather you are given a product designed to specs.
This is a great counter-argument to your theory, since that song (like all choices in that movie) was explicitly chosen to manipulate — to make you feel specific ways about the U.S. military and the Vietnamese villagers, to induce tension, etc.
The intent hasn't changed, you have. You'll discover this when re-experiencing old favorites and discovering that they've lost the magic because you've developed the tools to see behind the curtain.
Take a example of a clueless director putting rise of the valkeryies on a chopper scene in his movie without knowing about the scene in 'apocalyse now'. He knows the song as certain qualities to it and his intent is to bring these emotions across. Yet, is the watcher being manipulated despite this genuine intent?
What's more useful than making a useless distinction between what's genuinely fake and what's manipulative is looking at execution. Is the director being clumsily formulaic (common with many netflix shows now) or does it fit coherently as a work.
some points
* Shooting must be done on location
* All music must be incidental
* Genre movies are not acceptable