There are some interesting ideas in this. However music also might have evolved as a form of communication - for example birdsong, whale songs, or the songs var

There are some interesting ideas in this. However music also might have evolved as a form of communication - for example birdsong, whale songs, or the songs various insects make. They might not necessarily be communicating emotions - although maybe sometimes they are. It's a bit of a logical leap to decide all music evolved for emotion processing purposes, rather than say, language and communication purposes.