Not sure why this bothers you. Musical notation is, by necessity, a greatly simplified representation of the intended performance. Not only that, but the compos

Not sure why this bothers you. Musical notation is, by necessity, a greatly simplified representation of the intended performance. Not only that, but the composers themselves well understand that the interpretation of their notation is itself an artistic activity that is independent from the musical notation they write. There are thousands of recorded performances of any particular Bach or Beethoven work, every one different, sometimes very very much different. And none of them are “wrong”. We certainly don’t know for sure how Bach’s and Beethoven’s works were performed in their own days—there’s uncertainty over tuning, dynamics, and tempo, to say nothing of stylistic details—but we do know that the instruments they had available were very different, and yet their works are still great today, even though we can never reproduce what they were “supposed” to sound like.