I completely agree with your point though, sheet music is an element from Western "Music Theory", and has nothing to do with being able to make music. It definitely does help if you want to have musicians trained in that Western cultural practice to play your music, but not everyone cares about that.
Edit: my point about Mr Greenwood is that he is a huge part of the sound of Radiohead, as well as the other members.
I completely agree with your point though, sheet music is an element from Western "Music Theory", and has nothing to do with being able to make music. It definitely does help if you want to have musicians trained in that Western cultural practice to play your music, but not everyone cares about that.
Edit: my point about Mr Greenwood is that he is a huge part of the sound of Radiohead, as well as the other members.