Why no dialog-only subtitles?
In both Netflix and Amazon Prime, I often (always?) have a single option for English subtitles, which are closed captions ("English [CC]"). These includes descriptions of sounds and music that make the experience less enjoyable for me, e.g. "[Omnious music]". I can't possibly be the only one, one of my favorite cartoonists mocked it [1].
I wouldn't doubt that those descriptions are actually preferred by deaf people, but I'd like an alternative for myself.
Before streaming services, I barely knew this problem. Cable TV happily gave me dialog-only subtitles.
What puzzles me is, making dialogue-only subtitles from the closed captions they already have should be extremely cheap. A dumb bot removing everything that has brackets would do a flawless job almost all the time.
So why don't they do it, as a selectable option?
[1]: https://theoatmeal.com/comics/subtitles