People seem to have different expectations of recorded music vs live music. Even in the best of concert halls if you listen to the orchestra in "hi fi mode" you may well discover that some instrumental separations are not as overt as you would expect when listening to what we would call a "good" recording. However the visual input is a significant factor. If I look at the first violin, I can convince myself that I'm hearing that violin separately from the rest, but, with my eyes closed, all I really hear is a mass of violins, and almost no spatial separation between them.
So, recording engineers almost always spot-mic various parts of the ensemble, and then mix them together to create a recording that tries to recreate the experience, but in a way that makes sense without the visual context. Some are more successful than others. Recordings made using just a single pair of microphones can offer a great deal of realism, but often can sound muddled and confused. I suspect that our hearing adapts to the acoustic of the space we are in, so recording a live performance and reproducing it flawlessly somewhere else is probably impossible.
Add in the thorny issue of dynamic range, and things get even more problematic.