The appeal of this proposal is that it places the development of human language in
a social context. Early people must have lived in groups, if only because larger groups
offered better protection from attack.
Groups are necessarily social organizations and,
to maintain those organizations, some form of communication is required, even if it is
just grunts and curses. So, human sounds, however they were produced, must have
had some principled use within the life and social interaction of early human groups.
This is an important idea that may relate to the uses of humanly produced sounds.
It does not, however, answer our question regarding the origins of the sounds produced.
Apes and other primates live in social groups and use grunts