I agree - TOS. Period.
That has been built upon by fanfic, it was built upon by Tom DeSanto, and Richard Hatch - but the fanfic, DeSanto's
unfilmed efforts, even Richard's faithful 4 minute trailer are not canon (nor, actually, should they be).
Canon is the universe, mythology, characters, etc. that were presented to us in 1978-79. Obviously, this doesn't mean canon can't be presented in an updated fashion (which most of our detractors can't seem to understand).
(Sorry, Peter, my friend, but I found G80 so bad I, too, must disregard it in the face of what might yet be.)
I am
Dawg