To +1 the "no objective foundation": browse music theory research a bit! There's a ton of caveats and poor-sounding fits and whatnot for literally every approach, and there's endless discussion of it. E.g. have a MinutePhysics take on how the common 12 note western scale falls apart: https://www.youtube.com/watch?v=1Hqm0dYKUx4

And that's before even getting into completely alternate approaches, or how strongly harmonics affect perception: https://www.youtube.com/watch?v=VAgXpCK_4gA or https://www.youtube.com/watch?v=AZ8qZCGg4Bk

(maybe to clarify: there are objective aspects, in that sound is measurable. but there is nothing like a "grand unified theory" that covers all music, nor are roughly any of the popular ones internally consistent - it's far, far too varied for that, and physics often doesn't allow the desired consistency, causing more variety)