Principles that apply to human cultures, such as linguistic drift, don't necessarily apply to non-humans that have completely different psychologies.
For example, Troll speech appears to be almost instinctive in nature. Dwarfs are immortal (many of them anyway). Aldryami have some sort of proto-telepathic communion wit their forest. Each of these factors will completely change their linguistic development compared to humans.
Another factor is their non-human psychology. Sandy Petersen once explained it like this (I'm paraphrasing) in terms of Freudian psychology: Trolls only had an Id, Dwarves only have an Ego and Aldryami only have a Superego.
I
posted about this to the
Glorantha Digest back in 1998. I've copied in an extract from the post below, it starts with some definitions and then explains how I think they apply to the elder races. This doesn't mean I believe in Freudian Psychology, just that it can be a useful way to think about the races in Glorantha.
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Id : the, one of the three divisions of the psyche in psychoanalytic
theory that is completely unconscious and is the source of psychic
energy derived from instinctual needs and drives.
Ego : the, one of the three divisions of the psyche in psychoanalytic
theory that serves as the organized conscious mediator between the
person and reality especially by functioning both in the perception of
and adaptation to reality.
Superego : the, one of the three divisions of the psyche in
psychoanalytic theory that is only partly conscious, represents
internalization of parental conscience and the rules of society, and
functions to reward and punish through a system of moral attitudes,
conscience, and a sense of guilt.
Supposedly, trolls emphasise the id, mostali the ego and aldryami the
superego. ie :
Trolls are motivated by their instictual desires for food, offspring,
social power, etc. Their lack of an ego means that they have no real
sense of being a 'part of things', their lot in life is simply necessery
in order to get more food, beer, offspring, etc. The only way to prevent
them from satisfying their primitive needs is through force, or the
threat of it. They have no moral sense (superego), hence the brutal
nature of Troll society.
Mostali emphasize the Ego. Their whole purpose and raison d'etre is to
work on the world machine - their conception of reality. Their whole
lives are dedicated to fullfilling their need to feel usefull. Thier
personal needs (id) are of minimal importance and they have no moral
sense (superego) whatsoever. They simply do their job, whatever the
consequences - forever.
Aldryami emphasize the superego. Their entire lives are dedicated to the
protection and service of their mother Aldrya (internalization of
parental conscience), and their home forest. Their whole lives are
dedicated to the service of their home and people. Their personal
desires and needs (id) and sense of individual achievement and possition
in the scheme of things (ego) are superfluous to them.