In general, "canon" tends to be more of a fannish preoccupation than an actual thing. As I've mentioned before, the word "canon" appears nowhere in any publishing contract I've ever seen, and in all the years I've been writing and editing tie-in books I've never discussed "canonicity" with any licensor.
It's more of a practical consideration than a philosophical one. Star Trek novels aren't canon because nobody in their right mind would expect the tv shows and movies to be constrained by a paperback novel that a miniscule fraction of their audience has read, so one understands that the books can be contradicted at any time if the tv shows decide to do something else . . ..
It's more of a practical consideration than a philosophical one. Star Trek novels aren't canon because nobody in their right mind would expect the tv shows and movies to be constrained by a paperback novel that a miniscule fraction of their audience has read, so one understands that the books can be contradicted at any time if the tv shows decide to do something else . . ..